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[Review] GGL review extended until November 22nd
by Hartmut Kaiser 15 Nov '09

15 Nov '09

Hi all, The discussions around GGL are just start ramping up and we received only 2 (voting) reviews so far. Additionally, several people have been asking me off-list to extend the review period as they otherwise wouldn't be able to write a review in time. For these reasons the review period for the GGL library will be extended for another week. The review period will now end November 22nd. For everybody considering to vote: this would be a good time to write a review! Regards Hartmut GGL Review Manager ------------------- Meet me at BoostCon http://boostcon.com

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[GGL] Initial thoughts; how to register point types
by Phil Endecott 15 Nov '09

15 Nov '09

Dear All, Following is some initial feedback on GGL, after spending an hour or so with the docs. I hope to be able to complete a proper review over the next couple of days. The documentation seems very much focused on "how it works", which is of course useful for reviewing the design, but more "what it does" and "how to use it" content would help me to actually try it with some examples. For example, I have a Point<T> class and I would like to "teach" the library about it. From the "Design rationale" page I can see that a number of traits have to be defined, but I don't see a concise reference to what I need to do. Looking at the example "c01_custom_point_example.cpp" I see that there are some macros e.g. GEOMETRY_REGISTER_POINT_2D (not a Boost-style macro name by the way) but I don't see any documentation for what these do. I guess that it defines some traits specialisations, right? Does anyone know how to get Doxygen to create next/prev buttons for navigating between the pages in the e.g. "related pages" section? Is it possible to note which versions of the Boost library dependencies are needed? I'm not convinced that overloading e.g. distance() so that it works with all combinations of geometries is a good idea. If I wanted to know the distance from a point to a polygon I'd be happy to write distance_pt_to_poly(a,b). Having the overload makes it possible for me to accidentally pass the wrong things and get no error. And there is the question of what is meant by distance "to" a polygon - is it to the nearest point, or the centroid, etc? I believe that heterogeneous co-ordinate types (e.g. latitude and longitude of one type and altitude of another) are not supported, right? Regards, Phil.

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 14 Nov '09

14 Nov '09

> Thank you for the snappy reaction. Works lovely. Good news! > I hope you submit it for a formal review soon. Chances are that you > will wait for a review manager for a better part of the decade anyway. I have a review manager (David Abrahams) so we just need to negociate a date with the review wizards. It should definitely last not that long ;-)

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 14 Nov '09

14 Nov '09

> MSM 1.20 allowed writing a state machine with actions/guards which > modify some external state. <snip/> > I no longer instantiate the state machine directly and cannot pass > parameters to constructor and it seems that msm::back::state_machine > will not do this for me (after a quick glance at the definition it > seemed to me that msm::back::state_machine expects its template > parameter to be default constructible). > Is this wrong or am I missing something obvious? Is there some way I > could still achieve the old functionality? No you're not doing anything wrong, it's a use case I simply oversaw, so it's not your fault but mine ;-) So, I corrected the problem and : - added a templated constructor, with up to 5 arguments (can be changed with the BOOST_MSM_CONSTRUCTOR_ARG_SIZE define) - actualized the doc - thanked you for this in the acknowledgments You can download the change (in back/state machine.hpp) from the sandbox (http://svn.boost.org/svn/boost/sandbox/msm/) I tested your case and a few more so it should be ok now. Thanks a lot for the report. I'm happy you like the library. Regards, Christophe

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 14 Nov '09

14 Nov '09

>No, in this particular scenario I'd leave all the existing transitions in >place and just add the CDLoaded outer state. This is barely more work than >adding the flag, right? Ultimately, what I'm getting at is that your >justifying example in MsmSession_Handout.pdf could be better, because most >Statechart users wouldn't write the code you're implying they would. MSM vs. >Statechart aside, MSM users might be left with the question what flags are >good for when they can achieve the same with an additional outer state. >Again, flags are good, but the justifying example isn't. Ah now I think I now see what you mean. You're using direct entries and need therefore no change to the transitions. Point taken. I can change the example by adding another flag and giving it to one of the CDLoaded-states and one of the non-CDLoaded states, thus preventing the use of an outer state, eventhough it might make the example slightly more difficult than I intended. I really simply wanted to bring this new general concept. Regards, Christophe

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Detached threads and Futures
by ak1mbox-boost＠yahoo.ca 14 Nov '09

14 Nov '09

Hi, I wanted to judge people interest in the following feature and to see [hope :)] that maybe it is already scheduled to appear in the next thread library. I find it often useful to run blocking operations in a fully detached thread. These are often atomic IO operations which receive some input by copy and then if they succeed return some output or error if they fail. The functionality that I need can be described as follow: 1. Encapsulate some code, providing ability to send it any number of parameters 2. Receive notification when this code has finished doing whatever it was supposed to be doing and get the resulting output or error. 3. Be able to terminate all other threads without the fear of the detached thread causing a memory corruption. 4. [Optional] Indicate to the detached thread that it should try to interrupt its operation and exit but not really care if it can't at this point. With Anthony Williams Futures addition to the thread library implementing something like this should not be too difficult. Is this already in the works or would people be interested in someone taking this on as a standalone library and an addition to thread library? Thanks, Alex

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[mirror] C++0x version of the reflection library available
by Matus Chochlik 14 Nov '09

14 Nov '09

Dear list, I would like to announce that a new (alpha) version of the Mirror reflection library, re-written nearly completely from scratch in C++0x, is available at sourceforge.net for those interested, the code can be checked out from the SF repository: https://mirror-lib.svn.sourceforge.net/svnroot/mirror-lib/trunk/impl documentation pre-built with doxygen and DOT is available here: http://kifri.fri.uniza.sk/~chochlik/mirror-lib/html/ Based on a year and a half of user experience with the previous version (the one in Boost sandbox) there have been made several important changes. Just to mention a few: - The meta-objects should be more consistent with the base-level language - There is a run-time layer with an run-time interface very similar to the compile-time interface - Meta-object categories for tag dispatching have been added - "Local" names having parts of the nested name specifier stripped away if the Mirror's "using namespace" directive is used on the current (or parent) scope - C++0x features are extensively used to make things more straightforward - etc. This version does not yet implement all features from the previous version, like inherited class members, visitor-based traversals, meta-constructors and factory generators. These will be added in the near future. The library has been tested only with gcc (version 4.5.0 20091010) so I would be glad to hear about experiences with other compilers supporting C++0x. I would also appreciate any feedback, suggestions or other contributions. best regards, Matus

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[iostreams] 64bit compile issue
by Christoph 14 Nov '09

14 Nov '09

in boost/iostreams/detail/streambuf/indirect_streambuf.hpp:171: error: no matching function for call to 'max(int, std::streamsize&)' suggest fix: cast 2 to std::streamsize Best regards Christoph

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Halycon Days?
by Paul A. Bristow 14 Nov '09

14 Nov '09

http://tinyurl.com/yau3k57 see also youtube.com As Nom says - it is dead easy now there is a cable ;-) Paul --- Paul A. Bristow Prizet Farmhouse Kendal, UK LA8 8AB +44 1539 561830, mobile +44 7714330204 pbristow(a)hetp.u-net.com

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[Serialization] warnings and maybe a 'bug'
by Christoph Duelli 14 Nov '09

14 Nov '09

(I tried to file a ticket, but got cookie trouble. Therefore I post here. Sorry for the inconvenience.) i) warnings (unused parameter) (These warnings are with gcc, 4.2.1) boost/serialization/shared_ptr.hpp:116: warning: unused parameter 'file_version' boost/archive/shared_ptr_helper.hpp:110: warning: unused parameter 't' /boost/archive/detail/iserializer.hpp:474: warning: unused parameter 'ar' (and 't', same line) I also get lots of boost::archive::detail::<unnamed>::init_guid<XXXX>::g' defined but not used where XXXX is some class name of mine ii) maybe a 'bug' (code does no longer compile) Code that used to compile with Boost 1.40 does no longer compile with the 1.41 beta: (I had no time to investigate yet; in case it is obvious for you once you see the code I have decided to include this point in this posting): boost/archive/shared_ptr_helper.hpp:114: error: cannot convert 'const boost::serialization::extended_type_info_typeid<MEPfad>' to 'const boost::serialization::extended_type_info*' in return (where MEPfad is a class of mine) Best regards Christoph

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Beta build of PDF docs available for 1.41
by John Maddock 14 Nov '09

14 Nov '09

A beta build of the PDF documentation build for Boost-1.41 is available from the usual sourceforge page: https://sourceforge.net/project/admin/explorer.php?group_id=7586 in the Boost-docs/1.41.0 directory. Or directly from https://sourceforge.net/projects/boost/files/boost-docs/1.41.0/boost_pdf_1_…. If Boost authors would like to skim these for the usual SNAFU's that would be great. Otherwise I intend to release the final PDF build at the same time as Boost-1.41.0. Enjoy, John.

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[msm] Version 2.0 available
by Christophe Henry 14 Nov '09

14 Nov '09

Dear Boosters, I'm happy to announce the review-ready new version of Msm (2.0). Msm is a framework which enables you to build a Finite State Machine in a straightforward, descriptive and easy-to-use manner. The generated code is optimized for speed and will force you to use neither RTTI nor anything virtual. Msm supports most of UML state machine features: - state entry/exit - transition actions/guards - composite states - history - orthogonal regions - terminate states - deferred events - explicit entry/fork - entry/exit pseudostates - anonymous transitions - transition conflicts and much more. Msm v2.0 is a redesign of Msm v1.20 and offers a separation beetween front- and back-ends. There is currently one backend and several frontends: - the same frontend as Msm v1.20 - a variation of this frontend based on functors for actions - eUML, a boost::proto-based compile-time language allowing you to use UML notations directly inside your code, thus making writing code from a state machine diagram easier. eUML also comes in with a functional programming library similar to Boost.Phoenix, adapted to state machines. I'll be happy for any comment. You can find Msm v2.0 in: - the vault (http://www.boostpro.com/vault/index.php?directory=Msm) - the boost sandbox (http://svn.boost.org/svn/boost/sandbox/msm/) The documentation can be found at libs/msm/doc/index.htm and the code in the boost/msm subdirectory. The 1.0 and 1.10 are now retired. To close up the 1.x path, I'll bring a 1.21 with the latest bugfixes and then retire the 1.20 from the vault. Best regards, Christophe

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Boost bug sprint delayed until Wednesday, November 18th
by Marshall Clow 13 Nov '09

13 Nov '09

To allow time for the 1.41 release to complete, the start of the Boost Bug sprint has been delayed until next Wednesday, November 18th. That doesn't mean you can't work on bugs before that, though - just don't check fixes into svn until then. Find bugs, reproduce them, generate patches - all of those are fine! We started the last bug sprint with just over 800 open tickets. We finished with about 720 open tickets. Now (several months later) there are 854 open tickets. Useful reports: Active tickets https://svn.boost.org/trac/boost/report/1 Ticket counts by milestone https://svn.boost.org/trac/boost/report/21 Ticket counts by component https://svn.boost.org/trac/boost/report/19 Ticket counts by type https://svn.boost.org/trac/boost/report/20 Ticket counts by owner https://svn.boost.org/trac/boost/report/18 With 1.41 about to go out the door, we've still got a _bunch_ of tickets that were "to be resolved" by earlier milestones: Boost 1.36.0 101 Boost 1.37.0 45 Boost 1.38.0 64 Boost 1.39.0 89 Boost 1.40.0 139 That's more than half the active tickets! I'm sure that some of these have been fixed, or no longer apply. But which ones? -- Marshall P.S. If you're going to be participating in the sprint, please drop me a note.

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boost.python problem in release branch (GSoc work)
by Ralf W. Grosse-Kunstleve 13 Nov '09

13 Nov '09

I just found out that two boost.python tests (svn trunk and release) are not valgrind clean. I fear this could be a serious problem, although I've not seen actual failures apart from the valgrind diagnostics. What I know at the moment is: libs/python/test/properties.py libs/python/test/data_members.py produce valgrind errors with trunk revision 56305 but not 56304 (fedora 8 64-bit). The critical revision 56305 is: Merged 2009 GSoC work from sandbox-branches/bhy/py3k branch back into trunk. It is merged into the release branch already. Unfortunately, without revision 56305 boost.python does not work with Python 2.6.3 and 2.6.4, i.e. backing out rev. 56305 and some followup revisions would only replace one problem with another. How far along is the 1.41 release? Is there a chance it could be delayed for a few days? Ralf P.S.: I'll add this issue to the tracker when I get a chance (hopefully tomorrow).

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A fresh approach to iteration (Andrei Alexandrescu)
by Neal Becker 13 Nov '09

13 Nov '09

http://www.informit.com/articles/article.aspx?p=1407357&seqNum=7

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 13 Nov '09

13 Nov '09

>But you'd have to refactor an equivalent MSM Machine too (you'd need to introduce the flag), right? True, but adding one line to a few states is a lot less work than adding a composite, giving it a transition table and changing the transition table of the state machine.

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Official warnings policy?
by John Maddock 13 Nov '09

13 Nov '09

I'm *not* saying we should do this for 1.41, but should we have an official policy regarding compiler warnings and which ones we regard as "failures"? I realize these can get pretty busy-body at times, but if the user sees several pages of warnings when building Boost it doesn't look so good. So my suggestion would be that we have two test-runners (if we have any spare!) that build with warnings-as-errors, maybe: -Wall -pedantic -Wstrict-aliasing -fstrict-aliasing -Werror For gcc and: /W3 /WX for MSVC? Obviously these may prove to be far too busy-body, but is this worth a try? Cheers, John.

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Re: [boost] GGL Questions
by Bruno Lalande 12 Nov '09

12 Nov '09

Hi Peter, Thanks for your interest in GGL, and for trying to integrate it into your project. Lines and rays don't exist yet in GGL indeed. Adding them would basically consist in defining the corresponding concepts (like for polygon, segment, etc...) and then specialize the distance and intersection (to start with) algorithms for them, which is completely feasible. I'm personnally more video games oriented so I have already thought about the need of such things actually. As for directions, it's not there just because we didn't need it until now (there only exist a notion of orientation for points ranges traversal). I guess it would only be a traits to define and to use in algorithms that needed it. So to summarize, all those things are not yet there, but can easily be added. HTH Bruno

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[iostreams] Is anyone maintaining Boost.IOStreams?
by Richard Smith 12 Nov '09

12 Nov '09

I've just looked through the list of bugs for the iostreams library: https://svn.boost.org/trac/boost/report/14?USER=anonymous&page=4 >From a quick scan, it looks like this library is not being maintained any more. Is this true? Just scratching to scratch the surface, the following dozen bugs seem to be to all be trivial to fix. Many have patches, and the others have a sufficiently clear description that fixing them should only be a couple of minutes' work. 2094 -- has a patch that ought to be uncontroversial 2154 -- relates to code that seems not to exist any longer 2817 -- proposed resolution seems straightforward 2894 -- seems pretty straightforward 2932 -- would be trivial to fix, assuming a fix is desired 3010 -- appears to have been fixed 3011 -- has a patch that ought to be uncontroversial 3197 -- trivial suggestion to remove a compiler warning 3311 -- obviously an error and trivial to fix 3352 -- looks like a genuine subtle bug; includes a patch 3403 -- minor documentation niggle, complete with patch 3505 -- looks a genuine bug and includes patches Some of the other bugs look pretty serious to me, and I might be inclined to spend some time investigating them if I thought there was any realistic chance of the resulting patches being accepted. -- Richard Smith

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[Iostreams] Release notes
by Daniel James 12 Nov '09

12 Nov '09

Hi, I've added some release notes for Iostreams, but I don't really know much about the library so it'd be really helpful if someone who does could take a look at them. http://beta.boost.org/users/news/version_1_41_0 Daniel

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 12 Nov '09

12 Nov '09

Hi Andreas, >:-) You won't get any flames from me. Yes, I don't agree with some of the >points in MsmSession_Handout.pdf (e.g. 2.4, a user in his right mind would >put Stopped, Open, Paused and Playing into an outer CDLoaded state and then >only say if (state_downcast<const CDLoaded *> != 0)). True, it is a possible solution. But 1) you don't always want to refactor your state machine and 2) sometimes you can't. For example, to take the example in the Statechart documentation(http://www.boost.org/doc/libs/1_40_0/libs/statechart/doc/tuto…, if ( ( state_downcast< const NumLockOff * >() != 0 ) && ( state_downcast< const CapsLockOff * >() != 0 ) && ( state_downcast< const ScrollLockOff * >() != 0 ) ) could have been replaced by if(fsm.is_flag_active<IsOffState,Active::Flag_AND>()). And in this case I don't see a working refactoring solution. In my experience, the flag system has proven invaluable (to define, for example, several success states in a test case defined as a state machine). > However, although I haven't yet reviewed anything in-depth so far, I'm definitely impressed by the progress the library has made. I hope I'll find the time to contribute > an in-depth review. This would be great and your experience could prove invaluable. I'd be very thankful for it. > Out of curiosity, have you made any tests how many states compilers can manage without running out of memory? IIRC, a Boost.Statechart FSM with 128 states > and several hundred transitions was the most I was able to fit into one TU. Good point indeed. There are 2 limitations. First, Msm is based on boost::mpl::vector for the transition table and on boost::fusion::set to contain the states. Both have a default limit of 20, which can be extended to 50. This is the theoretical limit. Of course, you can add some vectorxxx.hpp headers (which I did). I tried up to 80 transitions and 80 states in one machine. The second limitation is the compiler. The test compiles on VC and g++, eventhough you might need lots of RAM (1.4GB with VC9, 400MB with g++) and 40-60s. The execution speed stays the same, thus proving the O(1) double-dispatch. I suppose that, while it must be possible to push this further, Boost.Statechart will likely break the compiler later than Msm. Regards, Christophe Henry

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CGL Questions
by Peter Schregle 12 Nov '09

12 Nov '09

Oops, I meant "GGL Questions" of course.

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CGL Questions
by Peter Schregle 12 Nov '09

12 Nov '09

We are thinking about replacing our geometric algorithms with the ones from GGL. We would want to somehow adapt our own geometric primitives so that GGL can work with them, and with points, line segments and polygons this works rather nicely. However, we also have a few other concepts, where we have not found a simple way to adapt them to GGL. 1) Line We consider a line being an infinite line in the mathematical sense, i.e. it does not have endpoints but extends into infinity on both sides. We want to be able to calculate the distance between such a line and a point, or the point of intersection ot two lines if it exists. 2) Ray We consider a ray being a line with one endpoint or origin, and extending into infinity. Here also we want to be able to calculate the distance between a ray and a point, or between two rays, or points of intersections etc. 3) Direction In order to implement a line and a ray as descibed above, we have introduced the concept of direction (which is basically the same as a direction unit vector, or an equivalent angle). Is there a concept like this in GGL? How could we calculate the angle of a line segment in GGL? Best regards Peter PS: By the way: I find the acronym GGL unfortunate. For me it feels a bit awkward, and I was typing it wrong all the time while preparing this text. Everytime I use it I'm forced to think hard about what it means, in order to get it right. I would prefer a more descriptive name like geometry or geolib, or something else that can be memorized better.

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getting started
by anirvana mishra 12 Nov '09

12 Nov '09

hello everybody, I have been using c++ for quite a long time but never thought of doing some development work for it.But now i think is the high time to contribute to this community and am looking forward for some good development work. can anyone tell as how to get started? Thanks -- All the best.

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Boost.Variant is not EqualityComparable
by brook＠biology.nmsu.edu 12 Nov '09

12 Nov '09

I just ran into the case that Boost Variant does not satisfy the EqualityComparable concept. While it provides operator==() and operator<() (and therefore is LessThanComparable), it does not provide operator!=(), which is required for the EqualityComparable concept. Is this by design or oversight? It seems reasonable to expect that a Boost Variant model this concept, but perhaps I am missing something. In case it is by oversight, the following patch seems to provide the missing operator. Cheers, Brook --- boost/variant/variant.hpp.orig 2009-05-13 21:21:59.000000000 -0600 +++ boost/variant/variant.hpp 2009-05-25 19:21:40.000000000 -0600 @@ -1681,6 +1681,8 @@ return rhs.apply_visitor(visitor); } + bool operator!=(const variant& rhs) const { return !(*this == rhs); } + bool operator<(const variant& rhs) const { //

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On Iteration
by Andrei Alexandrescu 12 Nov '09

12 Nov '09

My article with a draft name "Iterators Must Go (Ahead)" is now published on InformIt and mentioned on reddit.com. Due to the vagaries of posting time and reddit dynamics, the article didn't stay long on reddit's programming page so it got very few views and comments. http://www.reddit.com/r/programming/comments/a2hv3/ Please comment here and/or there and vote up if you liked it. Many thanks to the many Boost participants who reviewed the article prior to publication (see the article's last section for a full list). Andrei

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GGL Extensions
by Tom Brinkman 11 Nov '09

11 Nov '09

>> The GGL team proposes an extension model, very similar to what is used by GIL. I'm not sure that the extensions proposal worked very well for GIL. I'm not sure why. Probably it was too ambitious. Initially, just try encourage a small group of interested developers to work with you on extensions. When that number becomes too large, than start thinking about a more formalized system. If people see that there are a couple of really cool extensions that were intergrated, it might just encourage others to add extensions as well.

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Re: [boost] [msm] Version 2.0 available
by Christophe Henry 11 Nov '09

11 Nov '09

>Apologies if this is a silly question as I'm not familiar with earlier >versions of MSM, but how does this library different from Boost.Statechart? This is not a silly question but one which is begging for controversy ;-) I hope this is not starting a flame war, so from my understanding, there are advantages of using Msm on several points: - speed: Msm is much faster than statechart (see the performance page. Usually more than 20 times faster). - Design: * Msm makes heavier use of metaprogramming = longer compilation, higher speed * No RTTI and no virtual functions * Msm tries to follow the principles of declarativeness described in the book "C++ Template Metaprogramming". This leads to an interface, which is, in my opinion, easier to use. * Again in my opinion, entry/exit/guards are better with Msm. With Statechart, you have to write guard handling yourself and you don't get the event as parameter in the entry/exit. * Actions / guards are more reusable as you can provide a functor object * States are also more reusable as they don't know their containing state machine or other states (due to in-state transition-table definition in Statechart) - UML support. Msm supports forks, UML-conform event dispatching in orthogonal regions (which is that every region gets a chance to handle a given event), entry/exit pseudostates and anonymous transitions (transitions without an event). - Usage: Msm also supports different frontends. For example, eUML tries to hide metaprogramming as much as possible and tries to look like an UML diagram. This also help writing state machines easier with Msm. - Model-Driven approach. You will find in the doc directory my BoostCon paper (the only PDF) where I describe my analysis of MDD with both frameworks. But this is ultimately a matter of taste (as I will of course prefer Msm and Andreas will likely prefer Statechart), and you should take whatever fits your needs better and you are more comfortable with, so I'd advise you to look at both and see what you prefer (and even better, what I could do to improve Msm).

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[1.41.0] Release plans
by Beman Dawes 11 Nov '09

11 Nov '09

The plan to do a Beta 2 has been canceled at the urging of Robert Ramey, Eric Niebler, Paul Bristow, and others. We will stick to more-or-less the same schedule, but do a final release rather than a Beta 2 release. Please complete all merges to branches/release by 9 PM, Friday, November 13th, US Eastern time (02:00, Nov. 14 UTC) That's a day earlier than expected, but will be a lot more convenient for me if we can hold to it. Thanks, --Beman

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[integer] long long warning
by Vladimir Prus 11 Nov '09

11 Nov '09

Hi, if, in SVN trunk as of revision 57535, I go to libs/program_options/test and run: bjam warnings=all cxxflags=-Wextra I get a pile of warnings like this: ../../../boost/integer.hpp:145:24: warning: use of C99 long long integer constant These are actually only warnings that are now printed. Does anybody know what to do with them? Thanks, Volodya

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[BGL] Trying to get a correclty working Parallel BFS code
by Sandeep Gupta 11 Nov '09

11 Nov '09

Hi All, I have spent significant effort on parallel bfs. Currently its almost working. I would really appreciate some help to get it running correctly. I have attached the code (self contained and requires no input file). I think I have followed all the guidelines regarding distributed property maps mentioned in the docs ( http://www.osl.iu.edu/research/pbgl/documentation/graph/breadth_first_searc… ). I am out of ideas of where things can could have gone wrong. The correct output of input graph 0 --> 1 2 1 --> 2 3 2 --> 3 3 --> 4 6 4 --> 5 5 --> 6 --> should be Node ID : Level 0 : 0 1 : 1 2 : 1 3 : 2 4 : 3 5 : 4 6 : 3 But when ran with 2 processes the output comes out to be Node ID : Level 0 : 0 1 : 1 2 : 1 3 : 2 4 : 3 5 : 4294967295 6 : 3 Not sure why this is happening. Any suggestions or pointers would indeed be quite appreciated. Thanks for your time. -Sandeep

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[1.41, thread] small compile fix
by Tim Blechmann 11 Nov '09

11 Nov '09

hi all, trying the lastest release branch, i need the following fix to be able to compile the boost.thread sources ... would be great, if it could make it to the 1.41 release ... thnx, tim diff --git a/libs/thread/src/pthread/timeconv.inl b/libs/thread/src/pthread/timeconv.inl index 5ec3b17..50518c1 100644 --- a/libs/thread/src/pthread/timeconv.inl +++ b/libs/thread/src/pthread/timeconv.inl @@ -6,6 +6,8 @@ // boostinspect:nounnamed +#include <cassert> + namespace { const int MILLISECONDS_PER_SECOND = 1000; const int NANOSECONDS_PER_SECOND = 1000000000; -- tim(a)klingt.org http://tim.klingt.org Relying on the government to protect your privacy is like asking a peeping tom to install your window blinds. John Perry Barlow

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[1.41] cmake references in getting started
by Vladimir Prus 11 Nov '09

11 Nov '09

Hi, I went to fix a broken URL in getting started, and noticed that it now has references to CMake. I have a couple of questions: 1. Why is that reference made inside "Easy Build and Install" section, which was specifically writen by myself to describe the brand new "bootstrap + bjam" procedure? 2. Why is getting started including reference for experimental build system at all? The commit that added this is: r56947 | troy | 2009-10-17 07:33:43 +0400 (Sat, 17 Oct 2009) | 5 lines Replacement for boost.cmake on trunk and release: notices that it exists in the getting started guide. and I don't think the change was discussed. Thanks, Volodya

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Making toolchains easier to use
by Beman Dawes 11 Nov '09

11 Nov '09

I just tried to rebuild the Getting Started Guild on Windows 7, something I had done many times on XP. >cd \boost\trunk\more\getting_started >bjam The build failed. Inspecting the output turned up the message: python: can't open file 'C:/Program Files/Python26/Lib/site-packages/docutils/tools/rst2ht ml.py': [Errno 2] No such file or directory Ah! Because of the Win 7 upgrade, Python was reinstalled, and docutils needs to be installed again, too. Did that, but same problem. Ah! I remember from past pain. The docutils install doesn't install "tools", you have to do that by hand. Did that. That worked. Only half an hour of my time wasted. If I had been a new user or developer, it would have been much longer. Here is what I think should have happened: When the build failed, a dialog box or console message should have popped up telling me that docutils/tools aren't installed, and asking me if I wanted docutils/tools to be installed. If I answered yes, the necessary download and install steps should have been performed automatically. Furthermore, I think the same thing should happen for any tool used by Boost, whether it be for documentation or other purposes. I guess I mean any tool run via bjam, at least at first. This sort of auto install when needed is happens routinely for non-boost apps on my Ubuntu system. It saves much time and aggravation. Thoughts? --Beman

1 0

proposal interval container; ITL moved to the boost sandbox
by Joachim Faulhaber 11 Nov '09

11 Nov '09

Dear boosters, after completion of a lot of boostification work I moved my Interval Template Library to the boost sandbox in the boost project centric form: https://svn.boost.org/trac/boost/browser/sandbox/itl itl boost itl [itl_xt] [validate] libs itl [itl_xt] [validate] I have split up the original library into three parts: (1) itl, (2) itl_xt and (3) validate. Core part 1 'ITL' contains all interval container class templates. Only this part will be prepared for a formal submission. Part 2 'itl_xt' contains extended parts of the original library that do not belong to the core interval container data structures and might be proposed for later extensions. Part 3 'validate' contains the sources for the law based test automaton 'LaBatea' that has been used for an automated check of the ITLs correctness. Parts 2 and 3 do not yet conform boost standards and naming conventions and are not yet intended as contributions to boost. On the core ITL-part I have done the following: + Removed all virtual functions via introduction of mixins + Integrated deeper into boost libraries replacing own code by e.g. boost::type_traits and boost::mpl + Minimized the class template interfaces by transforming member functions into non member function templates. + Made interval containers more interoperable by overloading operators and global function templates. + Wrote a test suite using boost unit test tools. Tested for boost-instance types boost::date_time and boost::rational + Provided jamfiles to build and run examples and tests. + All examples and tests have been compiled, linked and run successfully with msvc_9.0 and gcc_3.4.4(cygwin). Next I am going to write boost style html-documentation. >From the boost web page I don't see a clear recommendation for a preferable way of doing that. Handcoded? Generated with BoostBook? Is there a reference library that has an exemplary standard documentation? Cheers Joachim

3 4

Re: [boost] [msm] Version 2.0 available
by Christophe Henry 11 Nov '09

11 Nov '09

Hi Eric, > Congrats! So is this a review request? Nudge, nudge. :) Yes. As soon as a review date is decided, there will be an announcement. Msm already has a review manager (Dave), we now have a powerful version, we just need a review date. >Do we really need another lambda? I hope that with a proto-based >Phoenix, we can retire all the mini-lambdas that have been >proliferating. (I'm guilty of this, too.) I expected that one :) Right now, yes I need. I need a tool to generate an mpl::vector of transitions (meaning with actions and guards), which I didn't manage to get to work with phoenix (maybe there is a way but I didn't see it). Of course, a proto-based phoenix would be of great help and if needed, I'd be happy to help on this. Regards, Christophe

2 1

GGL Review
by Tom Brinkman 11 Nov '09

11 Nov '09

GGL Review I'm very happy to see that that GGL is now ready for inclusion into boost. I have been following this library for the last couple of years. During that time, I have spent probably 5 hours looking over the code, reading the documentation and compiling the samples. I have a background in GIS applications. Count me as an enthusiastic supporter of this library and as a "yes" vote for inclusion into boost. I have no doubt that GGL will become one of the more popular libraries in boost. Thank you to Barend Gehrels, Bruno Lalande and Mateusz Loskot for submitting it to the public domain and to boost. The samples and tests are thorough and compile without errors or warnings on the latest version of the Intel compiler. The code follows all expected boost conventions. Tom Brinkman

2 1

Confused by regression testing "release" branch summary and unresolved issues
by Phil Richards 10 Nov '09

10 Nov '09

I expect the answer is blindingly obvious, but I've read http://www.boost.org/development/testing.html#Understanding and I don't understand. I'm looking at: http://www.boost.org/development/tests/release/developer/summary.html and: http://www.boost.org/development/tests/release/developer/issues.html I would expect that issues.html would list all the non-expected failures shown in the summary.html page, but it doesn't. (Even tough that's what the "Purpose" seems to claim.) The are a raft of gcc 4.4 failures (not marked as expected - some of them should be, btw), but there are no gcc 4.4 failures at all shown on the issues.html page. What is the relationship between these two pages? Is it documented anywhere? Is it actually an issue that the release has quite a lot of unresolved issues for gcc 4.4? Phil -- Phil Richards, <news(a)derived-software.ltd.uk>

3 4

[gil] Committing some code changes
by Christian Henning 10 Nov '09

10 Nov '09

Hi there, I'm in the process to add some non-invasive code changes for boost::gil. Since this is my first time to commit changes to boost I would like to make sure I'm doing it right. The changes would be added to the trunk. Is that the right place? I have done the obvious steps on my local machine. And besides adding comments when checking in my changes what other steps do I have to do? Thanks, Christian

2 3

Jamfile to control MSVC compiler options /Za and /Ze
by Paul A. Bristow 10 Nov '09

10 Nov '09

I have been taking my own medicine and trying to get Boost.math free of warnings with the /Za No MS extensions option. Mostly this is fine. project : requirements <toolset>msvc:<cxxflags>/Za # disable MS Extensions in Boost.Test. ... But a few tests *require* the extensions. I have tried to enable them for just one module thus: # pow test requires type_of that MS extensions. run pow_test.cpp ../../test/build//boost_test_exec_monitor : # command line : # input files : # requirements <toolset>msvc:<cxxflags>/Ze # Requires type_of which requires MS extensions. : test_pow ; but the compiler complains about deprecation (and most importantly, that later options do not override, so you can't specify /Za and them /Ze. compile-c-c++ ..\..\..\bin.v2\libs\math\test\test_pow.test\msvc-9.0\debug\asynch-exceptions-on \threading-multi\pow_test.obj cl : Command line warning D9035 : option 'Ze' has been deprecated and will be removed in a future release cl : Command line error D8016 : '/Za' and '/Ze' command-line options are incompatible Can any jam experts suggest a way round this (short of leaving the default enable extensions, and making an exception for all the vast majority of modules that are OK with /Za - too tedious to be attractive? Splitting into two classes of tests is also ugly.) Thanks. Paul --- Paul A. Bristow Prizet Farmhouse Kendal, UK LA8 8AB +44 1539 561830, mobile +44 7714330204 pbristow(a)hetp.u-net.com

2 1

[smart_ptr] make_shared_array/allocate_shared_array function templates
by Roman Kecher 09 Nov '09

09 Nov '09

Hi, I'm suggesting to add the following function templates to allow easy, exception-safe, creation of shared_array objects: - make_shared_array (very similar to make_shared which is used to create a shared_ptr) - allocate_shared_array (again, same functionality like allocate_shared) Is there any reason not to include these? Regards, Roman.

3 4

Time for another bug sprint (after 1.41 ships)?
by Marshall Clow 09 Nov '09

09 Nov '09

Earlier this year, we had a "bug sprint", where many people focused on fixing bugs in Boost. We managed to get the # of open tickets down from 800 to about 720. As of today, there are 820 open tickets in Trac. Is it time to focus on swotting bugs again? 1.41 is scheduled for release on 1-November; that's six weeks from yesterday. How about a bug sprint starting on 14-November, finishing on 22- November? That's two weekends - and finishes up before the American Thanksgiving holiday. -- Marshall P.S. This doesn't mean that people have to wait until November to fix bugs ;-) ;-)

12 25

[function] "paranoia" vs efficiency
by Domagoj Saric 09 Nov '09

09 Nov '09

As far as I can see boost::function<>::operator() performs: if (this->empty()) boost::throw_exception(bad_function_call()); before invoking the stored function (object)... My question is why or why only this "checked"/"safe" approach/method of invocation exists? Because this: - causes (extra) code branching - causes the compiler to insert exception throwing and handling code in surrounding/calling code (which need not otherwise be if the function stored in the boost function instance is itself nothrow) - inserts a call to the bad_function_call constructor - disables the compiler from inlining the function (MSVC atleast) - disables NVRO (MSVC atleast, http://msdn.microsoft.com/en-us/library/ms364057(VS.80).aspx#nrvo_cpp05_top… ) while at the same time I would most often consider calling a "null-function-pointer" a programmer error (that would therefor need to be "handled" with an assert not an exception), not a runtime 'unpredictable' exception... ...IMO the default should be not to include this check (i.e. use an assert) and provide a safeInvoke() type of method for those users and cases that actually require/want this type of check/behaviour... ...or atleast "it would be welcomed" if a non-checking unsafeInvoke() type of method would be provided for those that are 'sure' that the boost::function<> object is valid (for example in the line before i've just performed the same check to decide whether to call the function object or not)... -- "That men do not learn very much from the lessons of history is the most important of all the lessons of history." Aldous Huxley

8 18

[shared_ptr] Set pointer to null
by Mateusz Loskot 09 Nov '09

09 Nov '09

Hi, I'd like to make a custom deleter resetting pointer to 0 or other value (e.g. for debugging purposes) after resource has been deallocated. Would anyone suggest better option to this presented below? struct DeleterT { void operator()(::T* ptr) { ::DestroyT(ptr); // uses Visual C++ specific integer type *reinterpret_cast<__int64*>(&ptr) = 0; } }; Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

2 2

[iostreams] building zlib from source
by Vladimir Prus 09 Nov '09

09 Nov '09

I am working on improving detection of external dependencies (for 1.42), and I've noticed that the iostreams library is rather smart when it comes to building zlib (and bz2). It allows the user to specify either: - location of headers and libraries files, or - location of sources for zlib In the latter case, the sources will be compiled automatically. How important is the second use case? It's not very hard to support, and appears handy for Windows users, but if in practice, nobody cares, I can spend the time on other matters. Thanks, Volodya

2 3

[thread] Is interrupting a non boost.thread possible?
by Christoph Mathys 09 Nov '09

09 Nov '09

Hello I've a question about boost.threads: Is it possible to interrupt a thread for which I don't have a thread-object but which is using boost synchronization primitives (mutex, condition)? Thanks! Christoph

2 1

[1.41.0] Beta 2 plans
by Beman Dawes 08 Nov '09

08 Nov '09

Due to the issues exposed in the "Official warnings policy?" thread, there will be a second 1.41.0 beta, tentatively scheduled for Sunday, November 15th. Until Saturday, November 14th, the release branch is open for merges of low-risk bug fixes. In particular, fixes that clear compiler warnings are encouraged. Please do, however, make sure any changes are stable on trunk before merging them to release. I'll be traveling until Monday, with little or no email connectivity. So if questions arise, it would be great if the other release managers could step in with responses. Thanks, --Beman

5 5

ppc64 and OSX Snow Leopard
by Vladimir Prus 08 Nov '09

08 Nov '09

Folks, it was reported that in Snow Leopard, Apple has removed support for ppc64, and folks trying to use that receive fairly obscure errors. Some of Boost users were already confused by this. Now, this is of course more like Apple's problem, but here's a patch, against current trunk, to do a nice diagnostic of this in Boost.Build. The intention is that if you try to build just ppc64, or a two-way fat binary including ppc64 you get an error message, and if you try tobuild 4-way fat binary, ppc64 is skipped and you get 3-way binary. Can some of OSX users apply this patch to trunk and give it a try? If it works, I would like to merge to release branch. Thanks, Volodya

2 1

[1.41.0] Beta 1 release candidate
by Beman Dawes 07 Nov '09

07 Nov '09

1.41.0 beta 1 release candidates are available at http://boost.cowic.de/rc/ Before pushing the beta out to SourceForge, I'd appreciate it if several people would try the release candidate and report success or problems. Thanks, --Beman

16 38

compile problem with thread without rvalue references
by Bob Walters 07 Nov '09

07 Nov '09

I've just attempted a build of the current (1_40_0) boost distribution on a Solaris 10 machine, using the SunStudio12 compiler (cc). There seems to be a problem with boost::thread which is related to this compiler's lack of rvalue references. My build process has been: tar xzf boost_1_40_0.tgz cd boost_1_40_0 export BOOST_ROOT=`pwd` ./bootstrap.sh ./bjam toolset=sun address-model=64 The error I'm receiving: "./boost/thread/detail/thread.hpp", line 344: Error: boost::thread::thread(boost ::thread&) is not accessible from boost::move(boost::detail::thread_move_t<boost ::thread>). 1 Error(s) detected. "CC" -library=stlport4 -xO4 -mt -erroff=%none -m64 -KPIC -DBOOST_ALL_NO_LIB= 1 -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -DNDEBUG -I"." -c -o "bin.v2/l ibs/thread/build/sun/release/address-model-64/stdlib-sun-stlport/threading-multi /pthread/thread.o" "libs/thread/src/pthread/thread.cpp" move() seems to rely on a copy constructor for its returned thread when rvalue references aren't supported. There is no such constructor. Aside from changing compilers, is there any work around for this?

1 0

[system][filesystem v3] Question about error_code arguments
by Beman Dawes 07 Nov '09

07 Nov '09

A POSIX sub-group is looking at C++ bindings for POSIX. They are talking about a filesystem library binding at least loosely based on Boost.System, Boost.Filesystem, and C++ TR2. In looking at http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2009/n2838.html, "Library Support for Hybrid Error Handling (Rev 2)", they are concerned about specifying hybrid error handling like this: void f(error_code& ec=throws()); They would rather see it specified like this: void f(error_code* ec=0); One particular concern is that as currently worded, the N2838 proposal requires throws() return a null reference, which they see as relying on undefined behavior. I wasn't at the meeting where the LWG asked that a null reference be mandated; my reading of the standard is that it is unclear if returning a null reference is or isn't undefined behavior. Some of the core folks seem to think it is undefined, but compilers accept it. Although the reference form is usual for C++, the use of anything other than the default is limited, and usually in low-level code at that. Although I could personally live with either form, I'm leaning slightly toward the pointer form. Regardless, I'd like to hear Boosters views on the two interfaces above. Which do you prefer? Why? --Beman

24 102

[wave][function] Suppressing gcc-4.4.1 warnings
by John Maddock 07 Nov '09

07 Nov '09

Looks like the new type-punning warnings from gcc-4.4.1 are false positives (but I'd like someone else to confirm that!). The fixes below illustrate how to suppress them simply by declaring a temporary variable. HTH, John. Index: boost/wave/util/flex_string.hpp =================================================================== --- boost/wave/util/flex_string.hpp (revision 57230) +++ boost/wave/util/flex_string.hpp (working copy) @@ -1211,7 +1211,10 @@ }; Storage& Data() const - { return *reinterpret_cast<Storage*>(buf_); } + { + Storage* p = reinterpret_cast<Storage*>(buf_); + return *p; + } RefCountType GetRefs() const { Index: boost/function/function_base.hpp =================================================================== --- boost/function/function_base.hpp (revision 57230) +++ boost/function/function_base.hpp (working copy) @@ -316,11 +316,13 @@ new ((void*)&out_buffer.data) functor_type(*in_functor); if (op == move_functor_tag) { - reinterpret_cast<functor_type*>(&in_buffer.data)->~Functor(); + functor_type* f = reinterpret_cast<functor_type*>(&in_buffer.data); + f->~Functor(); } } else if (op == destroy_functor_tag) { // Some compilers (Borland, vc6, ...) are unhappy with ~functor_type. - reinterpret_cast<functor_type*>(&out_buffer.data)->~Functor(); + functor_type* f = reinterpret_cast<functor_type*>(&out_buffer.data); + f->~Functor(); } else if (op == check_functor_type_tag) { const BOOST_FUNCTION_STD_NS::type_info& check_type = *out_buffer.type.type;

6 9

[Boost] Introduction of numeric_adaptor
by Bruno Lalande 07 Nov '09

07 Nov '09

Hi, I would like to introduce the numeric_adaptor library that Barend and I have developed to address a recurring problem: integration of big numbers. We already talked about it in the past, when discussions about geometry would lead to robustness. We're introducing it now because of the upcoming formal review of GGL. The purpose of this library is to turn big-numbers proposed by the most well-known big number libraries into value-types, (almost) usable like any number. This way, a library developer who has a robustness sensible function to write can take numbers as template parameters, and use them in such a way that they can be a fundamental type or one of the value-types provided by numeric_adaptor. This is basically done by: - defining in all the big-number types all the operators needed to manipulate them like fundamental types - defining some free functions in the boost namespace for other operations (sin, cos, hypot, conversions...), which have an default overload for fundamental types and a specific overload for each big-number type proposed Example: template <class T> T my_robustness_sensitive_function(T value) { value /= 2; T value2 = boost::to<T>("123.0123456789"); value += boost::sqrt(value2); return value; }; This function is numeric_adaptor-ready. If T is a fundamental type, boost::to() will forward to boost::lexical_cast and boost::sqrt() will forward to std::sqrt(). If T is one of the big number types provided by the library, specific overloads will be used. The precision of the function will thus entirely depend on the type passed. If the user chooses to sacrifice precision and use fundamental types, there won't be any run-time overhead. If the user wants something more precise and uses a big-number type, the precision of the result will be the one of the chosen type. The library is extensible. Anyone can add a new big number type with all needed operators, and overload the free functions (or specialize a dedicated traits class - see boost::to()). Note: For conversions, we would have liked to extend boost::lexical_cast directly, but the library is not designed in that sense. That's why we wrapped it into a boost::to() function which is explicitly designed to be extended, via traits. Last week on this list list a generic convert_to was discussed and that system could be used alternatively. The library is in the Boost sandbox: https://svn.boost.org/svn/boost/sandbox/numeric_adaptor/ The library currently proposes 2 big number types: CLN and GMP. This is not a formal review request, rather a preview and a reference that we will possibly use during the review of GGL. However, we would really like to have your feedback and to know if such a library would make sense. Regards Bruno

7 13

boost::noncopyable errors are difficult to diagnose on MSVC
by Zachary Turner 07 Nov '09

07 Nov '09

Is there anything that can be done to improve the error messages generated by the compiler when a copy fails to be made due to a boost::noncopyable? I had just finished a sprint where I had typed close to 1,000 lines of code with tons of new classes and objects before trying to compile, and one of the classes I had entered was similar to the following: class foo { public: foo(boost::asio::ip::tcp::socket& socket) : socket_(socket) { } private: boost::asio::ip::tcp::socket socket_; }; Problem here is that I forgot to add a reference to the class member, it was by value so the compiler is going to generate an error since a socket cannot be copied. The error this generated from the compiler was: 1>Q:\include\boost\1.39.0\boost/asio/basic_io_object.hpp(92) : error C2248: 'boost::noncopyable_::noncopyable::noncopyable' : cannot access private member declared in class 'boost::noncopyable_::noncopyable' 1> Q:\include\boost\1.39.0\boost/noncopyable.hpp(27) : see declaration of 'boost::noncopyable_::noncopyable::noncopyable' 1> Q:\include\boost\1.39.0\boost/noncopyable.hpp(22) : see declaration of 'boost::noncopyable_::noncopyable' 1> This diagnostic occurred in the compiler generated function 'boost::asio::basic_io_object<IoObjectService>::basic_io_object(const boost::asio::basic_io_object<IoObjectService> &)' 1> with 1> [ 1> IoObjectService=boost::asio::stream_socket_service<boost::asio::ip::tcp> 1> ] The most I can possibly figure out from this is that it's related to a socket. but this hardly helped as I had been using socket stuff all over the place. It took a long time to track this down because there was zero information about even what source file the offending code was in. I know this is sort of catering to the compiler, but is there any trickery that can be done so that at least the compiler generates an error related to the source file the object was declared in?

4 4

ASIO
by Mohammed Rasmy 07 Nov '09

07 Nov '09

Hello, I am trying to do a POST request using Boost::Asio, of a variable x that holds an email address, and a variable y that holds the contents of a zip file. I couldn't find samples floating around and I'm unsure of how to proceed. I've come up with the following code: boost::asio::streambuf request; std::ostream request_stream(&request); wxString buffer = wxT("POST "); buffer += wxT("http://serveraddress.com"); buffer += wxT(" HTTP/1.1\r\n"); buffer += wxT("Host: serveraddress.com\r\n"); buffer += wxT("Accept: */*\r\n"); buffer += wxT("Connection: close\r\n\r\n"); buffer += wxT("email_address=test(a)test.com"); buffer += wxT("zip_file=")/*actual zip file data here?*/; request_stream << buffer.mb_str(); Note that I am using wxWidgets, wxT is nothing more than a way of defining strings there, and wxString is, well, a string. The above code compiles fine, but I am not sure how to add the zip file? Also would the above code work? I know it is working for a GET request but that's it. Please advise. Thanks for your time, Mohammed _________________________________________________________________ Keep your friends updated—even when you’re not signed in. http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/so…

4 4

[smart_ptr] Add make/allocate functions for boost::shared_array
by Roman Kecher 06 Nov '09

06 Nov '09

Hi, I was wondering if there's any reason not to include make_shared_array() / allocate_shared_array() in boost/make_shared.hpp (or maybe add boost/make_shared_array.hpp), along with the already existing make_shared() and allocate_shared() functions? Regards, Roman.

1 0

[swap] ruminations
by Jeffrey Hellrung 06 Nov '09

06 Nov '09

1) Would it be a good idea (aside from breaking backwards compatibility) to insulate boost::swap from being found via ADL? Consider another library, tsoob, which also has a swap intended to be used in the same manner as boost::swap (i.e., it finds a free function swap via ADL, falling back to std::swap or maybe some custom swap or whatever). Now tsoob::swap and boost::swap cannot be used in the same program (ambiguous call to overloaded function swap) if the associated namespaces of the type being swapped includes both boost and tsoob (certainly possible). What I'm thinking about is the possibility of creating a namespace boost::adl which contains (what would have previously been called) boost::swap, as well as any other similar free functions. So the only way to invoke boost::adl::swap is to make it explicit; it will never be found via ADL. Plus it helps document the underlying mechanism (ADL) of boost::swap. 2) Is there some way for boost::swap and tsoob::swap to coexist peacefully while retaining backwards compatibility for both? - Jeff

2 3

[graph] Usage (and possible removal) of LEDA and Stanford GraphBase adaptors for Boost.Graph
by Jeremiah Willcock 06 Nov '09

06 Nov '09

Are there any users of the LEDA and Stanford GraphBase adaptors for Boost.Graph? They are no longer actively maintained and there have been bug reports that the LEDA adaptor does not work with current versions of LEDA. If they are no longer used, Andrew Sutton and I will consider deprecating and/or removing them. Please reply if you would like these components kept in Boost.Graph. -- Jeremiah Willcock

1 0

[random] Seeding again
by Steven Watanabe 06 Nov '09

06 Nov '09

AMDG The attached patch allows random number generators to be seeded with any value. Currently linear_congruential and a few other generators can assert for some seeds. (For instance minstd_rand cannot be seeded with 0). For linear_congruential I am using the algorithm described in n2960, section 26.5.3.1/4. For linear_feedback_shift I use a similar idea, adding 2^(w-k) if the seed is less than 2^(w-k). The behavior of any code that was valid before, should be unaffected by this change. The patch includes test and documentation updates. The tests pass with gcc, msvc, and como. I think it's ready to go now. Okay to commit? In Christ, Steven Watanabe

1 0

New boost packaging suggestion for windows
by Julian Bangert 06 Nov '09

06 Nov '09

Hello, yesterday I tried to download the boostpro binaries for windows and I had to download over a gigabyte to get all configurations for VS 2008. Sadly the version also was outdated and in general not that great ( e.g. Installer quite bad to handle and you have to register to download ) . So I decided to build from source and package it for a few friends who also needed these binaries. I managed to compress boost_1_40 ( no source except headers, no python AFAIK , but everything else you get with a standard build ) from over 900MB down to 37MB by using 7z. I uploaded it here https://obliviononline.com/pub/boost/boost_1_40_0.7z . Should boost use this form of releasing binaries in the future for windows ? Alternatively, you could endorse this form, like boostpro is endorsed right now and I could host it on google code, etc . An easy to set up ( just unzip this file ) binary distribution would make compiling boost-dependent software much easier. I would be willing to distribute future releases compatible with VS 2005 and 2008 in this form. Yours, Julian Bangert __________ Information from ESET NOD32 Antivirus, version of virus signature database 4551 (20091028) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

12 20

Boost.Python release testing failures
by Steve M. Robbins 06 Nov '09

06 Nov '09

Hi, I'm running Boost nightly regression tests on a 64-bit Debian linux platform for quite some time. I've recently added gcc 4.4 and Boost.Python is failing miserably; c.f. http://tinyurl.com/yl7yjkv If I click on a test result URL, such as for "andreas_beyer" [http://tinyurl.com/yft8k3o] I'm redirected ("See boost/bin.v2/libs/python/build/gcc-4.4/debug") which shows that the compile succeeded, but nothing more [http://tinyurl.com/yft8k3o] Digging into the bjam.log file, it turns out these tests are skipped because the Boost.Python library failed to build. It would be nice to improve the error reporting to make this clear. The compilation error is: "g++-4.4" -ftemplate-depth-128 -std=c++0x -O0 -fno-inline -w -g -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_PYTHON_SOURCE -I".." -I"/usr/include/python2.5" -c -o "/home/steve/Packages/boost/upstream/testing/release/results/boost/bin.v2/libs/python/build/gcc-4.4/debug/object/function_doc_signature.o" "../libs/python/src/object/function_doc_signature.cpp" ../libs/python/src/object/function_doc_signature.cpp: In static member function 'static boost::python::str boost::python::objects::function_doc_signature_generator::pretty_signature(const boost::python::objects::function*, size_t, bool)': ../libs/python/src/object/function_doc_signature.cpp:238: error: no match for 'operator%' in '"%s %s(%s%s%s%s)" % std::make_tuple(_Elements&& ...) [with _Elements = boost::python::str&, const boost::python::api::object&, boost::python::str, boost::python::str, boost::python::str, std::string](((const boost::python::api::object&)(& f->boost::python::objects::function::m_name)), ((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = int, V = size_t, U = boost::python::api::object](((const int&)((const int*)(&0))), ((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads))))))))))), ((boost::python::str&&)(&((n_overloads != 0u) ? ((((size_t)arity) != n_overloads) ? boost::python::str(((const char*)" [,")) : boost::python::str(((const char*)"[ "))) : boost::python::str()))), ((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = size_t, V = unsigned int, U = boost::python::api::object](((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads)))), ((const unsigned int&)((const unsigned int*)(& arity)))))))))), ((std::string&&)(& std::basic_string<char, std::char_traits<char>, std::allocator<char> >(n_overloads, 93, ((const std::allocator<char>&)((const std::allocator<char>*)(& std::allocator<char>())))))))' ../boost/python/object_operators.hpp:104: note: candidates are: boost::python::api::object boost::python::api::operator%(const boost::python::api::object&, const boost::python::api::object&) ../libs/python/src/object/function_doc_signature.cpp:249: error: no match for 'operator%' in '"%s(%s%s%s%s) -> %s" % std::make_tuple(_Elements&& ...) [with _Elements = const boost::python::api::object&, boost::python::str, boost::python::str, boost::python::str, std::string, boost::python::str&](((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = int, V = size_t, U = boost::python::api::object](((const int&)((const int*)(&0))), ((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads))))))))))), ((boost::python::str&&)(&((n_overloads != 0u) ? ((((size_t)arity) != n_overloads) ? boost::python::str(((const char*)" [,")) : boost::python::str(((const char*)"[ "))) : boost::python::str()))), ((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = size_t, V = unsigned int, U = boost::python::api::object](((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads)))), ((const unsigned int&)((const unsigned int*)(& arity)))))))))), ((std::string&&)(& std::basic_string<char, std::char_traits<char>, std::allocator<char> >(n_overloads, 93, ((const std::allocator<char>&)((const std::allocator<char>*)(& std::allocator<char>())))))), ((boost::python::str&)(& ret_type)))' ../boost/python/object_operators.hpp:104: note: candidates are: boost::python::api::object boost::python::api::operator%(const boost::python::api::object&, const boost::python::api::object&) ../libs/python/src/object/function_doc_signature.cpp:262: error: no match for 'operator%' in '"%s %s(%s%s%s%s) %s" % std::make_tuple(_Elements&& ...) [with _Elements = boost::python::str, const boost::python::api::object&, boost::python::str, boost::python::str, boost::python::str, std::string, boost::python::str](((const boost::python::api::object&)(& f->boost::python::objects::function::m_name)), ((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = int, V = size_t, U = boost::python::api::object](((const int&)((const int*)(&0))), ((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads))))))))))), ((boost::python::str&&)(&((n_overloads != 0u) ? ((((size_t)arity) != n_overloads) ? boost::python::str(((const char*)" [,")) : boost::python::str(((const char*)"[ "))) : boost::python::str()))), ((boost::python::str&&)(& boost::python::str::join(const T&) const [with T = boost::python::api::object_slice](((const boost::python::api::object_slice&)((const boost::python::api::object_slice*)(& boost::python::api::object_operators::slice(const T&, const V&) [with T = size_t, V = unsigned int, U = boost::python::api::object](((const size_t&)((const size_t*)(&(((size_t)arity) - n_overloads)))), ((const unsigned int&)((const unsigned int*)(& arity)))))))))), ((std::string&&)(& std::basic_string<char, std::char_traits<char>, std::allocator<char> >(n_overloads, 93, ((const std::allocator<char>&)((const std::allocator<char>*)(& std::allocator<char>())))))), ((boost::python::str&&)(&(cpp_types ? boost::python::str(((const char*)"")) : boost::python::str(((const boost::python::str&)((const boost::python::str*)(& ret_type))))))))' ../boost/python/object_operators.hpp:104: note: candidates are: boost::python::api::object boost::python::api::operator%(const boost::python::api::object&, const boost::python::api::object&) ...failed gcc.compile.c++ /home/steve/Packages/boost/upstream/testing/release/results/boost/bin.v2/libs/python/build/gcc-4.4/debug/object/function_doc_signature.o... I hope this helps the Boost.Python maintainers to fix it. Let me know if you need more info. Thanks, -Steve

3 3

[rdb] 0.2.00 - bind parameter and result + dynamic sql
by Jean-Louis Leroy 05 Nov '09

05 Nov '09

I have uploaded version 0.2.01 to the vault. It contains two new major features. The first is the ability to bind parameters to variables allocated outside the prepared statement, e.g.: // in the following examples the database contains: // id first_name name age // 1 Homer Simpson 37 // 2 Marge Simpson 34 BOOST_FIXTURE_TEST_CASE(prepared_select_bind_integer_param, springfield_fixture) { person p; BOOST_AUTO(st, db.prepare(select(p.first_name).from(p).where(p.id == _))); integer id_param; st.bind_parameters(id_param); id_param = 1; BOOST_RDB_CHECK_SELECT_RESULTS(st.execute(), "((Homer))"); id_param = 2; BOOST_RDB_CHECK_SELECT_RESULTS(st.execute(), "((Marge))"); } The possibility of passing parameters to execute() remains but this is more efficient, as execute(params) binds the parameters each time it is called. Likewise, it is now possible to bind results, e.g.: BOOST_FIXTURE_TEST_CASE(prepared_select_bind_results, springfield_fixture) { person p; BOOST_AUTO(st, db.prepare(select(p.id, p.first_name).from(p))); integer id; varchar<30> first_name; st.bind_results(id, first_name); BOOST_AUTO(results, st.execute()); results.fetch(); BOOST_CHECK(!id.is_null()); BOOST_CHECK_EQUAL(id.value(), 1); BOOST_CHECK(!first_name.is_null()); BOOST_CHECK_EQUAL(string(first_name), "Homer"); results.fetch(); BOOST_CHECK(!id.is_null()); BOOST_CHECK_EQUAL(id.value(), 2); BOOST_CHECK(!first_name.is_null()); BOOST_CHECK_EQUAL(string(first_name), "Marge"); } The second feature is dynamic creation of statements. A fully static system doesn't make it possible e.g. to create a search form, where you enter (optional) values and the program returns a list of matching values. Dynamic statement parts (lists of expressions, columns, tables) are created via the make_dynamic() function. It returns a "stable" type, which does not incorporate the full type information for the encapsulated sql code. This makes it possible to create dynamic collections of sql constructs and pass them to a statement. Static and dynamic parts can be miexed freely. For example: BOOST_FIXTURE_TEST_CASE(prepared_select_bind_dynamic_integer_param, springfield_fixture) { person p; dynamic_boolean predicate = make_dynamic(p.id == _); BOOST_AUTO(st, db.prepare(select(p.first_name).from(p).where(predicate))); integer id_param; dynamic_values params; params.push_back(make_dynamic(id_param)); st.bind_parameters(params); id_param = 1; BOOST_RDB_CHECK_SELECT_RESULTS(st.execute(), "((Homer))"); id_param = 2; BOOST_RDB_CHECK_SELECT_RESULTS(st.execute(), "((Marge))"); } Here a dynamic boolean expression is used in the where clause. It contains a parameter so it is necessary to pass a collection of dynamic values when executing the statement. Here is a more complex example: BOOST_FIXTURE_TEST_CASE(prepared_select_dynamic_tables, springfield_fixture) { person p("husband"); person spouse("wife"); partner::qualified link; dynamic_expressions exprs; exprs.push_back(make_dynamic(spouse.first_name)); dynamic_tables tables; tables.push_back(make_dynamic(spouse)); tables.push_back(make_dynamic(link)); dynamic_boolean predicate = make_dynamic(p.id == link.husband && link.wife == spouse.id); BOOST_AUTO(st, db.prepare(select(p.first_name, exprs).from(p, tables).where(predicate))); varchar<30> him; dynamic_values results; varchar<30> her; results.push_back(make_dynamic(her)); st.bind_results(him, results); BOOST_AUTO(cursor, st.execute()); cursor.fetch(); BOOST_CHECK(!him.is_null()); BOOST_CHECK_EQUAL(string(him), "Homer"); BOOST_CHECK(!her.is_null()); BOOST_CHECK_EQUAL(string(her), "Marge"); } Here the projection is partly dynamic, and so is the table list and the where clause. Static entities are checked at compile-time as usual, and dynamic entities at run-time - and thus may fail with an exception. However, the system is designed to (attempt to) minimize the risk of type mismatch in the dynamic parts - no casts are required in client code (nor in the implementation ftm). The test suite contains several other examples of dynamic statements (see test_odbc_dynamic.cpp). At this point I feel that all the major features in the scope of this project have been addressed. Okay a lot is still missing - e.g. more types (currently only integer and varchar are supported), constraints, count() and such functions, group/order by... - but all these should be easy to implement in the existing framework. And the thing needs cleaning up and documentation, plus testing on Unix. J-L

1 0

[filesystem][system] Usage guideline request
by Andrey Semashev 05 Nov '09

05 Nov '09

Hi, I'm updating our software from Boost 1.33 to 1.40 and one of the major issues I encountered is using exceptions from Boost.Filesystem. The exception basic_filesystem_error has changed its interface in a breaking way, as it now relies on Boost.System error codes. I'm not aware of whether this change has been announced properly and the API deprecation period has been offered. And that is actually not what bothers me mostly. The 1.33 version of Boost.Filesystem offered a number of unified error codes that our code used to react accordingly. For example, there were error codes out_of_space_error, already_exists_error, which were used on any platform supported by Boost.Filesystem. Now, with Boost.System in place, there are at least three sets of errors: system::errc, system::windows_error and system::linux_error, although, I assume, the latter is an addition to system::errc. In order to check for the older out_of_space_error I now have to write something like this: catch (basic_filesystem_error& e) { if ( e.code() == system::errc::make_error_code( system::errc::no_space_on_device) #if defined(WIN32) || e.code() == system::windows_error::make_error_code( system::windows_error::disk_full) #endif ) { // out_of_space_error } } Is this the right way to do this? Is there a portable way to do it? I tried to find a better way in the Boost.System documentation, but was highly disappointed as there is virtually no documentation at all. Also, no examples available for this library. I wonder how this library passed the review in the first place.

2 2

[1.41.0] Release branch open for low-risk merges
by Beman Dawes 05 Nov '09

05 Nov '09

branches\release is open for low-risk merges. Use your own judgment as to what "low-risk" is, but as always stability on trunk is one of the criteria. Towards the middle of next week we will take a look at where we stand as far as the freeze for final release. We can always decide to do a second beta, too. But please do any outstanding merges as soon as you are sure they are stable, rather than waiting until the last moment. Thanks, --Beman

3 3

[1.41.0] Release branch closed for all changes; beta RC tomorrow
by Beman Dawes 05 Nov '09

05 Nov '09

The release branch is closed for all changes. Unless someone objects strenuously, I'll build a release candidate for the beta tomorrow (Tuesday) morning, eastern US time. --Beman

8 14

[timer] an accumulating_timer would be nice
by Thorsten Ottosen 05 Nov '09

05 Nov '09

Hi, For some measurements, it would be nice with a timer with the following interface class accumulating_timer { public: accumulating_timer(); // don't start timing void start(); void stop(); double elapsed() const; }; The benefit here would be that we don't have to convert to seconds until that data is actually needed. Thoughts? -Thorsten

1 0

Boost Graph Library license (boost_1_40_0/libs/graph/LICENSE)
by Troels Walsted Hansen 05 Nov '09

05 Nov '09

Hi Doug and boost developers, In a message to this mailing list on 2006-03-12 ( http://lists.boost.org/Archives/boost/2006/03/101902.php) Doug mentioned that the Boost Graph Library had been entirely converted to the regular Boost Software License (http://www.boost.org/LICENSE_1_0.txt) However, even the latest boost 1.40.0 distribution contains a file called boost_1_40_0/libs/graph/LICENSE which contains the text of the old The Boost Graph Library "Artistic License". This is slightly confusing because it could be interpreted to mean that the Boost Graph Library is still covered by the Artistic License. Can you confirm that this file is dead and void? Can it be removed from the boost distribution to avoid any license ambiguity? Thanks, Troels

2 1

Reminder: ** Please don't overquote **
by David Abrahams 05 Nov '09

05 Nov '09

I'm seeing lots of messages that quote entire threads before adding a paragraph (or sometimes just a sentence) out-of-line. Please try to keep the list and its archives readable by pruning the quoted text before posting (http://www.boost.org/community/policy.html#quoting) Thanks -- Dave Abrahams Meet me at BoostCon: http://www.boostcon.com Boost Moderator http://www.boost.org

1 0

Re: [boost] [1.41.0] Beta 1 available
by Vladimir Prus 04 Nov '09

04 Nov '09

Daniel James wrote: > On Wed, Nov 4, 2009 at 1:45 PM, Ovanes Markarian <om_boost(a)keywallet.com> wrote: >> Hello *, >> the link in the docs to Property Tree points to the wrong location. >> http://beta.boost.org/doc/libs/1_40_0/libs/property_tree/index.html >> if changing to http://beta.boost.org/doc/libs/1_41_0/libs and clicking to >> Property Tree the link points to: >> http://beta.boost.org/doc/libs/1_41_0/libs/property_tree/index.html >> But this file does not exist either. > > The documentation isn't uploaded to the site until the final release. > You can see the property tree documentation in the download. The beta > site isn't really meant for general use. Speaking of documentation: 1. It appears that http://www.boost.org/boost-build2/index.html is still broken. Is there any way to figure why? 2. Looking at http://beta.boost.org/users/news/version_1_41_0 I do not see a section 'Build System' -- which is present in boost_1_41_0.qbk Is this expected? - Volodya

2 1

[1.41.0] Beta 1 CMake 1
by troy d. straszheim 04 Nov '09

04 Nov '09

The boost.cmake beta that shadows upstream releases is out. Docs: http://sodium.resophonic.com/boost-cmake/1.41.0.beta1.cmake1/doc Tarballs and zipfiles: http://sodium.resophonic.com/boost-cmake/1.41.0.beta1.cmake1 Followups on the boost-cmake list please. -t

1 0

1.41.0 cmake options
by Neal Becker 04 Nov '09

04 Nov '09

If I wanted to try cmake, can I use cmake with my favorite options? I'm currently using: bjam -sHAVE_ICU=1 -sEXPAT_INCLUDE=/usr -sEXPAT_LIBPATH=/usr/lib64 -- layout=tagged threading=single,multi stage Can I set these options with cmake, and if so, how?

2 2

Re: [boost] New boost packaging suggestion for windows
by Julian Bangert 04 Nov '09

04 Nov '09

Hello, I just noticed an error crept into my earlier posted link: The correct link for google is: http://boost-win-bin.googlecode.com/files/boost_1_40_0-vc9-preview.7z I would appreciate any comments on this distribution, so that I could pack it up with an installer and really "release" it. Again, this distribution pretty much contains all of boost - all configurations for a single version of Visual C++, without Python or MPI, but is very tightly pakced into around 30 MB ( a 30th of the current boostpro distribution size ) Yrs, Julian Bangert

2 1

loglite - A logging library
by JD 04 Nov '09

04 Nov '09

Hello, It's been a while since a discussion about logging hasn't ran on the boost mailing list. I have a small logging library implementing some of the requirements that were previously deemed desirable during the discussion we had here a couple of years ago. Find it here : http://code.google.com/p/loglite/ I've removed all mention to boost in the code, cause I've made some design choice that wouldn't fit with the boost philosophy. Please have a look and let me know what you think could be improved. An example : [example removed because of the now infamous anti-top-posting gmane feature] Regards, JD

7 14

Boost using MS Visual Studio 2010 - C2027
by Christofer Weßeling 04 Nov '09

04 Nov '09

Hi! I've tried to build Boost using MS Visual Studio 2010, but I'm getting a C2027 error. Basically the problem is known and located as a problem of the MS compiler: https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?Feedb… Is there still a workaround? Greets! Christofer Here comes the error....: 1>c:\projekte\boost\1.40.0\boost\bind\bind.hpp(1657): warning C4180: qualifier applied to function type has no meaning; ignored 1> c:\projekte\boost\1.40.0\boost\bind\bind.hpp(1691) : see reference to class template instantiation 'boost::_bi::add_cref<Pm,I>' being compiled 1> with 1> [ 1> Pm=FileTime<UTC> (__thiscall File::* )(void), 1> I=1 1> ] 1> c:\projekte\ps3controlmodule\productformattingasd\fileadmin.cpp(346) : see reference to class template instantiation 'boost::_bi::dm_result<Pm,A1>' being compiled 1> with 1> [ 1> Pm=FileTime<UTC> (__thiscall File::* )(void), 1> A1=boost::arg<1> 1> ] 1>c:\projekte\boost\1.40.0\boost\bind\bind.hpp(1691): error C2027: use of undefined type 'boost::_bi::add_cref<Pm,I>' 1> with 1> [ 1> Pm=FileTime<UTC> (File::* )(void), 1> I=1 1> ] 1> c:\projekte\ps3controlmodule\productformattingasd\fileadmin.cpp(347) : see reference to class template instantiation 'boost::_bi::dm_result<Pm,A1>' being compiled 1> with 1> [ 1> Pm=FileTime<UTC> (__thiscall File::* )(void), 1> A1=boost::arg<2> 1> ] 1> 1>Build FAILED.

3 7

Build boot 1.40.0 on IBM z/OS (EBCDIC)
by norbert.hanke＠bluewin.ch 03 Nov '09

03 Nov '09

Hi folks, I am trying to build boost on the IBM Mainframe on z/OS USS. I successfully modified the jam bootstrap script and have a running bjam binary now. But when trying to build the boost libraries, I get the error below. Does anybody have a hint what to look for? EBCDIC character encoding on my machine might be the reason: digits 0-9 are encoded as character values 240-249, but I have no idea where to start looking. regards, Norbert > ./bjam /home/u250672/boost_1_40_0/tools/build/v2/util/numbers.jam:22: in numbers.check from module numbers error: 03 in 03 1 17 error: is not a number /home/u250672/boost_1_40_0/tools/build/v2/build/version.jam:50: in version-less from module version /home/u250672/boost_1_40_0/tools/build/v2/build/version.jam:102: in version.check-jam-version from module version /home/u250672/boost_1_40_0/tools/build/v2/util/path.jam:172: in join from module path /home/u250672/boost_1_40_0/tools/build/v2/util/path.jam:207: in path.root from module path /home/u250672/boost_1_40_0/tools/build/v2/util/path.jam:247: in path.glob from module path /home/u250672/boost_1_40_0/tools/build/v2/tools/types/register.jam:25: in load from module types/register /home/u250672/boost_1_40_0/tools/build/v2/kernel/modules.jam:283: in import from module modules /home/u250672/boost_1_40_0/tools/build/v2/tools/stage.jam:19: in load from module stage /home/u250672/boost_1_40_0/tools/build/v2/kernel/modules.jam:283: in import from module modules /home/u250672/boost_1_40_0/tools/build/v2/tools/builtin.jam:25: in load from module builtin /home/u250672/boost_1_40_0/tools/build/v2/kernel/modules.jam:283: in import from module modules /home/u250672/boost_1_40_0/tools/build/v2/build-system.jam:11: in load from module build-system /home/u250672/boost_1_40_0/tools/build/v2/kernel/modules.jam:283: in import from module modules /home/u250672/boost_1_40_0/tools/build/v2/kernel/bootstrap.jam:138: in boost-build from module /home/u250672/boost_1_40_0/boost-build.jam:16: in module scope from module

2 3

Temporary objects
by DE 03 Nov '09

03 Nov '09

hi all unfortunately i'm totally out of time now so i only write my proposal and an example forgive me for that the code #include <algorithm> template<typename type> class temporary : public type { temporary() : type() {} temporary(temporary &a) : type() { using std::swap; swap(static_cast<type&>(*this), static_cast<type&>(a)); } template<typename other> temporary(const other &a) : type(a) {} temporary &operator=(temporary &a) { using std::swap; swap(static_cast<type&>(*this), static_cast<type&>(a)); return *this; } template<typename other> temporary &operator=(const other &a) { type::operator=(a); return *this; } }; example1 temporary<huge_type> foo(const huge_type &a) {//returning temporary object temporary<huge_type> ret; //or even 'ret(a)' //doing something... return ret; } //... huge_type result; result = foo(bar); //somewhere in code only one copy operation -- assignment operator return by value copying overhead is eliminated with help of swap() example2 struct my_type { //... my_type(temporary<my_type> &a) { this->swap(a); } //... my_type &operator=(temporary<my_type> &a) { this->swap(a); return *this; } //... }; temporary<my_type> process(const my_type &item) { temporary<my_type> ret; //processing item... return ret; } //... my_type result = process(item); //somewhere in code //or result = process(item); no temporary object handling overhead at all return by value, copy-construct and assign from temporary objects for free! thank you for attention

7 21

[interval container (itl)] A pretty large bitset
by Joachim Faulhaber 03 Nov '09

03 Nov '09

Dear list! In thread http://lists.boost.org/Archives/boost/2009/06/152786.php Zachary Turner posted an article about a compressed bitset, that uses run-length defined intervals to achieve a compact representation of large bitsets that are useful for managing huge file allocation tables. As I mentioned in a reply to this article, Zach's compressed bitsets, in their basic ideas, are quite similar to itl::interval_sets: They allow for compression of large quantities of elements as long as they occur in (large) uninterrupted chunks. As Zach pointed out, this nice behavior is completely spoiled, if we would want to handle a set like {1,3,5,7,9,...,2(k-1)} or as bitset '0101010101...01' Here, the capability of usual bitsets to compress elements that are distributed over only small ranges can neither be applied to Zach's compressed bitset nor to an itl::interval_set of the Interval Template Library. As a new use case of interval containers I have developed a *large_bitset* class template on top of itl::interval_map that is able to combine interval compression *and* bitset compression. It is, for instance, capable of representing the bitset mentioned above '01010101...010' a b a: bit 0 b: bit 2^64-1 containing 2^63 bits (or elements) with just *one* internal interval associated to only *one* value of 64bit length ;) Curious?? Find the documented example code in my updated library docs at http://www.herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/boost_itl/pr… While the documented class template 'large_bitset', for reasons of a short presentation, is only a minimal one, you can find a more elaborated version as 'interval_bitset' in the sandbox at https://svn.boost.org/svn/boost/sandbox/itl/boost/itl_xt/interval_bitset.hpp I'd like to ask Zachary Turner to comment on the use case. Can this be useful in your field? Moreover I'd like to encourage everyone to give feedback on my interval container library, report problems, bugs and share suggestions. If you find this stuff useful please volunteer as review manager for the submitted library Boost Interval Containers. Note, that the new example on 'large_bitsets' is not yet included in the library submitted for review in the vault but it is contained in the sandbox. I am currently preparing an update of the review version of the itl, that is adjusted and corrected for the feedback, suggestions and patches that I have received during the last weeks. I will integrate further feedback and account for bug reports if you have any. Best regards Joachim

4 7

[tree?] STL like tree data structure in boost?
by Nil Geisweiller 03 Nov '09

03 Nov '09

hi, any idea if there is in boost a similar tree data structure such as Kasper Peeters's tree.hh http://tree.phi-sci.com/ ? thanks Nil

5 7

Parallel Tree Merge
by Biddiscombe, John A. 03 Nov '09

03 Nov '09

If I have a representation of a tree and I have sub-portions of it spread across a number of processes (but the whole tree represents a well-formed and simple tree structure). Is there a reasonably straightforward way of doing this using BGL or PBGL. I had hoped that it might be as simple as defining some templated tree structure and using the add operator after gathering pieces onto one node. (The tree structure could be represented as XML where the root would exist on all processes, different sub-nodes and leaves and would occur on different processes - a simple xml merge would probably suffice for my needs right now). If examples using boost libraries ((p)BGL/MPI) or other similar combination exist and anyone can point me to resources I'd be most grateful. (I'm not an expert with BGL so will need some do some learning...) Thanks JB -- John Biddiscombe, email:biddisco @ cscs.ch http://www.cscs.ch/ CSCS, Swiss National Supercomputing Centre | Tel: +41 (91) 610.82.07 Via Cantonale, 6928 Manno, Switzerland | Fax: +41 (91) 610.82.82

3 3

Cross-platform date/time problems
by Zachary Turner 03 Nov '09

03 Nov '09

Hello list, Apologies for the cross-posting, this originally went to the boost-users list but it got no responses, and then I also realized it was actually more appropriate here. Suppose I have a cross-platform agent that communicates with a server. Agent from platform X sends a message to the server which contains a date/time. Server sends a message to another agent running platform Y with the same date/time. In practice X/Y are always either windows/linux or linux/windows. The server always tells the agent which platform's native format the time is represented in, so there should be no problem. Ideally I'd like to write the following code: ptime time; if (msg.is_from_windows()) { time = from_ftime<ptime>(msg.time()); } else { time = from_time_t(msg.time()); } But this doesn't work because from_ftime<> is not defined on linux. If from_ftime<> is already templated on the FILETIME type, is there any reason it needs to be #ifdef'd out on non-windows platforms? I mean, a FILETIME is really just a uint64, can't the templated function also just operate on a boost::uint64_t? Zach

3 8

#3541 Support <boost/ptr_map.hpp>
by Olaf van der Spek 02 Nov '09

02 Nov '09

Hi, https://svn.boost.org/trac/boost/ticket/3541 Could a forward header file be created such that #include <boost/ptr_map.hpp> works? The extra ptr_container directory is hard to remember..., I always have to look it up. boost/ptr_* looks much more natural. Greetings, Olaf

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Re: [boost] loglite - A logging library (JD) (Zachary Turner)
by Tan, Tom (Shanghai) 02 Nov '09

02 Nov '09

>I've always found it was easiest to do something like: >namespace boost { namespace filesystem { >#if defined(_WIN32) || defined(WIN64) > typedef wpath npath; >#else > typedef path npath; >#endif >} } >and then use boost::filesystem::npath everywhere. Performance isn't >generally the bottleneck when dealing with the filesystem, but why even >bother with so many behind-the-scenes conversions when you can just as >easily store everything in the type the O/S is expecting in the first place >with a simple typedef? That's handy when only OS API is involved, but if you have to use it other Libraries which are only string-ready, e.g. LIGLITE, you have no choice. Even Some popular Boost libraries are only for strings, Boost.Test is one.

1 0

The C++ Post-Processor
by Christian Schladetsch 02 Nov '09

02 Nov '09

Hello, This is a general post about C++. Why is it that the pre-processor (PP) is the source of so much disdain, and yet it is the first resource exploited to 'fix' problems with C++? Why has the PP received so little attention over the years, from its early use as M4? This is a message to the powers that be: the PP is a powerful tool. It provides a 'context-cutting' mechanism for creating and extending solutions. It is a true "meta-programming" system built right into C++. No other language I can think of has a PP. This is often viewed as being a good thing, but I wonder more and more as I get older that a good PP is in fact needed to span some otherwise very difficult boundaries. Other languages are "dynamic" inasmuch as they reflect classes and allow for runtime changes to types and instances. I think we all here agree that this ability is counter to building firm, safe and efficient software. But the PP is similar to that, allowing a degree of dynamicy not otherwise available. Specifically, by exposing concepts to the PP we can leverage reflection and synthesis while building on inheritance and conglomeration. I don't have a point as such; I just wanted to raise the idea of developing M4 and the PP past where it is. There is a lot of low-hanging fruit there. This is evidenced by the fact that a lot of other languages are or can be transliterated to C++. Rather than thinking of C++ as the output, we could be thinking of C++ as the input. Perhaps a way forward for C++ is a good PP and a standards-based implementation of C++ in C++ so it can embed itself. I've written a number of languages, and in each I've had to address the issue of pre-processing. The latest attempts have resulted in a system where it parses and executes via AST input to produce an output that is then parsed by the same system to produce an AST that is then walked to eventually produce machine code. I think this model is best, and would be delighted to see some similar movements in the PP/C++. We have Boost.Wave to start with... Why not give it real Expressions? Loops? Scopes? Classes? Templates? memory management? IO? Is there any interest in a Boost.C++ ? Regards, Christian

15 30

[optional] layout
by Domagoj Saric 01 Nov '09

01 Nov '09

why is boost::optional laid out so that the bool comes before the object's placeholder/storage? this takes up to 7 extra bytes of storage with default alignement and, more importantly, it forces pointer offset adjustment/calculation when accessing a boost::optional<> through a pointer (and trying to access the actual contained object)... it also makes life harder for those of us keen to hackery ;) because it makes the address of an optional different from the address of the actual object within the optional... ps. it would be 'cool' if all of the functionality from boost::optional<> not related to the 'is initialized' bool (conditional destruction, etc...) could be extracted into a separate class (usefull for cases where you have to delay/in-place construct an object but are certain that you will construct it by the point where it needs to be used or destroyed...so you do not need the 'conditional' overhead)... -- "That men do not learn very much from the lessons of history is the most important of all the lessons of history." Aldous Huxley

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Re: [boost] loglite - A logging library (JD)
by Tan, Tom (Shanghai) 01 Nov '09

01 Nov '09

> Please have a look and let me know what you think could be improved. The first thing I notice is that it does not support std::wstring directly. It's a big problem in my case I use wide-character in all my applications, which simplifies dealing with UTF-16 adopted by Modern Windows platforms. If I need to any string info from my program, I'll have to convert from UTF16(represented as std::wstring) to UTF8 so that it could be working well with LOGLITE. That's inconvenient. Offtopic, I am expecting boost::filesystem V3 for this very same reason.

3 2

[ANN] CLI command line interface compiler for C++
by Boris Kolpackov 29 Oct '09

29 Oct '09

Hi, I am pleased to announce the first public release of CLI. CLI is an open-source (MIT license), cross-platform command line interface compiler for C++. It allows you to specify the options that your program supports, their types, and default values. For example: include <string>; class options { bool --help; std::string --name = "example"; unsigned int --level | -l = 5; }; This specification can then be automatically translated to C++ classes that implement parsing of the command line arguments and provide a convenient and type-safe interface for accessing the extracted data. For example: #include <string> class options { public: options (int argc, char** argv); options (int argc, char** argv, int& end); bool help () const; const std::string& name () const; unsigned int level () const; ... }; int main (int argc, char* argv[]) { options o (argc, argv); if (o.help ()) print_usage (); if (o.level () > 4) cerr << "name is " << o.name () << endl; ... } It is easy to start using CLI in your application since there are no external dependencies. You can compile your command line interface to C++ and simply add the generated files to your project's source code. For a five minute introduction to CLI, see the "Hello World" example in the CLI Getting Started Guide: http://www.codesynthesis.com/projects/cli/doc/guide/#2 More information, documentation, and source code distributions are available from the project's web page: http://www.codesynthesis.com/projects/cli/ Enjoy, Boris -- Boris Kolpackov, Code Synthesis Tools http://codesynthesis.com/~boris/blog Open-source XML data binding for C++: http://codesynthesis.com/products/xsd XML data binding for embedded systems: http://codesynthesis.com/products/xsde

4 6

Re: [boost] [Boost-users] at_thread_exit() never getting called
by vicente.botet 29 Oct '09

29 Oct '09

Hi, ----- Original Message ----- From: "cowwoc" <cowwoc(a)bbs.darktech.org> To: <boost-users(a)lists.boost.org> Sent: Wednesday, October 28, 2009 7:33 PM Subject: Re: [Boost-users] at_thread_exit() never getting called > > > I think https://svn.boost.org/trac/boost/ticket/2739 prevents it from > working. > > Gili > > > Steven Watanabe-4 wrote: >> >> AMDG >> >> cowwoc wrote: >>> I am registering boost::this_thread::at_thread_exit() against one of my >>> threads. When the main thread exits using "return 0" the at_thread_exit >>> hook >>> never gets invoked. Is this normal? >> >> It's supposed to work for the main thread... For me yes, but it dosn't works. The example attached to the ticket show the problem. >>> Is there a way to hook the main thread >>> shutting down? >>> >> >> On windows you can use on_thread_exit(). >> The patch worked when I summited it. Anthony, I've see that you have started to integrate the patch for the thread attributes. Do you plan to integrate this patch also? Thanks, Vicente

2 4

what is the interest of In Place factory
by rodrigue pons 29 Oct '09

29 Oct '09

Hello, I was looking about the boost In Place Factory to resolve a problem i got, and there is something i don't understand: what is the advantage of this lib? For example: I get a class A, wich constructor is: A( int, const string& ); And an another class, C, that contains an A*. C provides a method to construct this A*: void C::BuildA( int i, const string & str ); wich will be called this way: instance_of_C.BuildA( 1, "test" ); If now i use the boost In Place Factory, the member function C::BuildA will become: template<class InPlaceFactoryT> void C::BuildA( InPlaceFactoryT const& factory ) wich will be called this way: instance_of_C.BuildA( 1, "test" ); We can see here that with or wothout the In Place Factory, the code is exactly the same. So i guess there is something i didn't understand. But what?

2 2

boost.math
by rodrigue pons 29 Oct '09

29 Oct '09

Hello, i need to implement the computation of huges series. These series are made of floats, and thus the error propagates. The problem is that the main constrain is the execution time, thus i must use the more "native" type possible. Is boost.math offer a solution to minimize this error? Which type of float (float, double, any structure?) must i use? Thanks.

5 10

[spirit][regex] rxstrlit/regex_p with wchar_t strings
by Adam Badura 29 Oct '09

29 Oct '09

Is it possible to use rxstrlit/regex_p with wide character strings (wchar_t based)? Or even better, with arbitrary char type/char traits pair? I tried this with suggested example (http://www.boost.org/doc/libs/1_40_0/libs/spirit/classic/example/fundamenta…) and after converting to wchar_t what was required and compiling it run successfully. But it generated a lot of warnings about converting wchar_t to char in headers that looked like regex headers. So I guess it worked only because the wchar_ts in the example are actually chars. If I changed the example to use wchar_t which have no corresponding char values the example would likely fail. In the end I have a string with templated char type and traits type (just like with string and iostream library). And I want to match it against grammar build from (among others) strings with the same char type and traits type. Can I force regex in Spirit to do that? Adam Badura

1 0

Why BOOST_HAS_DECLSPEC is not defined under MingW?
by Artyom 29 Oct '09

29 Oct '09

Hello, I've noticed following lines under boost/config/platform/win32.hpp #if !defined(__GNUC__) && !defined(BOOST_HAS_DECLSPEC) # define BOOST_HAS_DECLSPEC #endif Why? GCC provides support of declspec, Why it is specifically undefined? It can auto-export symbols but it does not work when static members involved. Thanks, Artyom

1 0

Re: [boost] New boost packaging suggestion for windows
by Julian Bangert 29 Oct '09

29 Oct '09

Hello, > Sadly, the only point being discussed so far is the online registration. > What I find to be at least as annoying is the size of the package. And > by that I'm not (only) referring to the memory or bandwidth. The most > important issue is the burden of having to deal with such an amount of > data, even if I'm only interested into a relatively small part of boost. > My package contains everything in one archive. These 37MB offer quite good compression and you can choose what you wish to extract. > I wonder whether there is still any thought or even effort spent on > breaking boost up into individual components that can be built, tested, > and ultimately also packaged separately. Any news on that ? > > Thanks, > Stefan > Well, a lot of Linux distributions already have this ( all the libboost- packages in debian for examples ) . In W32 it is possible even with BoostPro and in my distribution you can selectively extract libs. Tell me if this is wanted/appreciated and I can write a GUI frontend to automatically install components. I just uploaded the files to 2 sites for distribution, at least one of which should be up at any given time: 1) ( the mirror, but the preferred location ) http://boost-win-bin.googlecode.com/files/boost_1_40_0-vc9-preview.7z* 2) ( main site, but not on a good machine) https://obliviononline.com/pub/boost/ *After a few people confirm that this works for them they should be considered stable and I would build for other C versions as well. Then they could also be mentioned in getting started. * *Thanks, Julian Bangert __________ Information from ESET NOD32 Antivirus, version of virus signature database 4553 (20091028) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

2 1

[dbc] Interest in Design By Contract for C++?
by Lorenzo Caminiti 29 Oct '09

29 Oct '09

Hello all, Is there any interest in a library that supports Design By Contract (DBC) for C++? All DBC features of the Eiffel programming language are supported by this library, among others: 1) Optional compilation and runtime checking of preconditions, postconditions, and invariants. 2) Subcontracting for derived classes. 3) Use of "old" in postconditions. 4) Automatic contract documentation (integrated with doxygen or similar tools). EXAMPLE This is part of the Stack4 DBC example presented for Eiffel in the book "Object Oriented Software Construction", B. Meyer, 1997. It has been coded for C++ using this library. #include <dbc.hpp> // This library. template<typename T> class Stack4 DBC_INHERIT_OBJECT(Stack4<T>) { public: Stack4(const int& n): capacity_(0), count_(0), representation_() DBC_CONSTRUCTOR( (private) (template)(Stack4)( (const int&) (n) ), { // Constructor preconditions. DBC_ASSERT(n >= 0, "non negative capacity"); }, { // Constructor postconditions. DBC_ASSERT(self.now.capacity() == n.now, "capacity set"); DBC_ASSERT(self.now.empty(), "is empty"); }, { // Constructor body. capacity_ = n; representation_.resize(capacity_); }) virtual ~Stack4() DBC_DESTRUCTOR( (public) (virtual) (template)(Stack4)(), { // Destructor body (do nothing). }) void remove() DBC_MEM_FUN( (public) (void) (template)DBC_COPYABLE(Stack4) (remove)(), { // Member function preconditions. DBC_ASSERT(!self.empty(), "not empty"); }, { // Member function postconditions. DBC_ASSERT(!self.now.full(), "not full"); DBC_ASSERT(self.now.count() == (self.old.count() - 1), "count decreased"); }, { // Member function body. --count_; }) ... // The rest of the Stack4 class. private: int capacity_; int count_; std::vector<T> representation_; DBC_INVARIANT(Stack4, { DBC_ASSERT(self.count() >= 0, "count non negative"); DBC_ASSERT_STREAM(self.count() <= self.capacity(), "count no greater than capacity", err << "count " << self.count() << " bounded by capacity " << self.capacity()); DBC_ASSERT( self.capacity() == int(self.representation_.capacity()), "capacity consistent with vector capacity"); DBC_ASSERT(self.empty() == (self.count() == 0), "empty when no elements"); if (self.count() > 0) DBC_ASSERT( self.representation_.at(self.count() - 1) == self.item(), "if positive count, item at top"); }) }; Example Notes: a) The somewhat strange syntax of the macro-based API (i.e., DBC_CONSTRUCTOR(), DBC_DESTRUCTOR(), and DBC_MEM_FUN()) uses a C++ preprocessor sequence of tokens "(public) (void) (template) ..." (this library internally uses Boost.Preprocessor to implement these macros). This library also provides a code-based API (dbc::fun::constr<>, dbc::fun::destr<>, and dbc::fun::mem<>) that can be used instead of the macro-based API but more setup code needs to be written by the programmers. b) This library also internally uses Boost.MPL mainly for typetraits, to support "old" in postconditions but only for types marked DBC_COPYABLE(), and for static assertions checking for library missuses (e.g., incorrect preprocessor sequence of tokens passed to the macro-based API). c) This library requires contracts to be written together with the class declaration (as contracts are part of the class specification). The class definition (function body) instead can either be written together with the contracts in the class declaration (like in the example above) or it can be written separately from the class declaration (i.e., this library maintains for function bodies the same C++ feature that allows to separate function's declaration and definition). Cheers, Lorenzo

5 9

[integer] Compilation failed in Visual Studio
by Adam Badura 28 Oct '09

28 Oct '09

Following simple program: #include <boost/integer_fwd.hpp> int main() { return 0; } does not compile in Visual Studio 2008 with Boost 1.40.0. Compilation errors are following: 1>d:\libraries\boost_1_40_0\boost\integer_fwd.hpp(70) : error C2039: 'long_long_type' : is not a member of 'boost' 1>d:\libraries\boost_1_40_0\boost\integer_fwd.hpp(70) : error C2065: 'long_long_type' : undeclared identifier 1>d:\libraries\boost_1_40_0\boost\integer_fwd.hpp(70) : error C2913: explicit specialization; 'boost::integer_traits' is not a specialization of a class template 1>d:\libraries\boost_1_40_0\boost\integer_fwd.hpp(73) : error C2913: explicit specialization; 'boost::integer_traits' is not a specialization of a class template Adam Badura

6 9

[thread][thread_specific_ptr]
by Sid Sacek 28 Oct '09

28 Oct '09

In VC++ and GCC a user creates global TLS like this: VC++ __declspec( thread ) int tls_1; GCC __thread int tls_2; But using the boost library boost::thread_specific_ptr< int > tls_3; doesn't provide an initialized global variable as one would expect from thread-local-storage. Using tls_3 crashes the program if it's not pre-initialized to some object. The implication is that every time a new thread is created, it needs to first instantiate all global TLS objects. Am I not understanding the intentions of this class? Is there a proper or intended way of using this class? I couldn't find any example code in the boost archives. Thanks, -Sid

2 2

Can we suppress integer_traits warnings?
by John Maddock 27 Oct '09

27 Oct '09

If you have a program that simply includes boost/integer_traits.hpp and is compiled with g++ -pedantic you get a bunch of warnings: ./boost/integer_traits.hpp:164:57: warning: use of C99 long long integer constant ./boost/integer_traits.hpp:164:73: warning: use of C99 long long integer constant ./boost/integer_traits.hpp:170:62: warning: use of C99 long long integer constant ./boost/integer_traits.hpp:170:62: warning: use of C99 long long integer constant And no matter where I insert __extension__ I can't seem to get gcc to suppress these:-( Any ideas? BTW I'm asking because this came to me as a - somewhat misplaced - bug report: https://svn.boost.org/trac/boost/ticket/1451. Thanks, John.

7 17

[task in sandbox] memory leak?
by Jeffrey Hellrung 27 Oct '09

27 Oct '09

All: A colleague of mine is trying to use the proposed Boost.Task library in the sandbox, but he is observing some memory leaks. See forwarded email below and attached cpp file. Does anyone have any information or suggestions for him? I agreed to query the list for him, but if this becomes too involved, I'll ask him to subscribe and communicate directly. Thanks! - Jeff -------- Original Message -------- Subject: Boost.task memory leak Date: Tue, 27 Oct 2009 15:14:44 -0700 From: Paul Jones <pajones(a)gmail.com> To: Jeffrey Hellrung <jhellrung(a)ucla.edu> References: <7f0a1570910271324o3dcb2d9xb361501267b7a5db(a)mail.gmail.com> This code leaks memory on my system: - gcc version 4.4.1 (Ubuntu 4.4.1-4ubuntu8) - Boost 1.40 - boost.task-0.3.0 When this code is run you can observe the program's allocated memory steadily increasing in the system monitor. The output displays the number of (undestroyed) functor objects when all the pool has completed all of its tasks. This seems to be capped at 64, so this isn't the source of the leak. The maintainer's name is Oliver Kowalke. But I couldn't find his email address. Paul

1 0

asio library
by Peter Foelsche 27 Oct '09

27 Oct '09

Out of curiousity (reading somebody comment here regarding socket calls) I looked into the asio library and found the following example code below. My question is: What is the use of the socket object created in the first line? I think this line must always be followed by some more code. Because of this it does not make sense, that a library exports this functionality. boost::asio::ip::tcp::socket socket(io_service); boost::system::error_code ec; socket.open(boost::asio::ip::tcp::v4(), ec); if (ec) { // An error occurred. }

4 7

Proposal for Library to perform dependency injection
by Adam Young 27 Oct '09

27 Oct '09

Having had a career that has bounced me between a few languages, I have had the opportunity to work with a couple of tools in the Java world that didn't see, to have analogues in C++. One of these is the inversion of control containers, of which Spring is one of the best known. Ken Fowler suggested the term "Dependency Injection" as a way to better describe how inversion of control is performed, and I prefer his term. I've written a fairly simple dependency injection framework in C++ that seems to make proper use of the C++ Language. It is not attempting to do any COM like component model. Rather, it allows the developer the ability to cleanly separate the Object usage from the construction policy. I've posted the code on Sourceforge at https://sourceforge.net/projects/cpp-resolver/. I have not yet taken the time to get it into proper format for a Sandbox project, but will do that next if there seems to be enough interest in the project. I wrote up the philosophy behind the design here: http://adam.younglogic.com/?p=146 The code is currently g++ only, although I've attempted to use only core language constructs. It has no dependencies on other libraries other than stl collections. Any constructive feed back will be most appreciated. Adam

2 2

[conversion] Release v0.4: Replace function template specialization by ADL
by vicente.botet 27 Oct '09

27 Oct '09

Hi, I have just released the version 0.4 of Boost.Conversion , which includes since my last publicly announced version 0.3: Replace function template specialization by ADL A Source class is convertible to a Target class if: * Either: A function with the signature convert_to<Target>(Source const&, boost::dummy::type_tag<To> const&) is available via argument dependent lookup * Or: A template specialization of boost::conversion::convert_to<Target, Source> exists for Target and Source * Or: Target is copy constructible from Source (default implementation) The template function convert_to allows to convert a source type to a target type, using argument dependent lookup to select a specialized convert_to function if available. If no specialized convert_to function is available, boost::conversion::convert_to is used. The generic convert_to function requires that the elements to be converted are assignable and copy constructible. It is implemented using the Target copy construction from a Source or the Source conversion operator Target - this is sometimes unavailable. For standard types, we can not add a specialized convert_to function on the namespace std. The alternative to using argument dependent lookup in this situation is to provide a template specialization of boost::conversion::convert_to for every pair of standard types that requires a specialized convert_to. You can found all the detail for dowloading, documentation, ... in http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction#Boost.Conve… I'd appreciate it if people could take a look, test it on their compiler and give me some feedback. Thanks to Edward Diener for showing me that multiple assignments should be taken in account. Thanks also to Jeffrey Hellrung and Robert Stewart for showing me that Boost.Conversion should use also ADL. BTW, I'm looking for a review manager. Anyone around here who would like to volunteer? Best regards, _____________________ Vicente Juan Botet Escribá

1 0

[system][filesystem v3] A possible error_code argument compromise
by Scott McMurray 27 Oct '09

27 Oct '09

2009/10/20 Beman Dawes <bdawes(a)acm.org>: > > One particular concern is that as currently worded, the N2838 proposal > requires throws() return a null reference, which they see as relying > on undefined behavior. > So it sounds like the idea solution is something that looks like a reference to the caller, for shortness of typing, but looks like a pointer to the implementation, to ease checking and avoid the weirdness of null references. struct optional_error_code_ref { optional_error_code_ref() : p_() {} optional_error_code_ref(optional_error_code_ref const &ecr) : p_(ecr.p_) {} optional_error_code_ref(error_code &r) : p_(&r) {} error_code &operator*() const { return *p_; } error_code *operator->() const { return p_; } operator safe_bool() const { return safe_bool(p_); } private: error_code *p_; }; Then the call is done the same was as before: error_code ec; foo(ec); But it's obvious to check, and never deals in null references: void foo(optional_error_code_ref ec = optional_error_code_ref()) { ... if (ec) { ec->value = bar; } else { throw bar_exception(); } ... } It would of course be better spelt qux<error_code&>, but I'm not sure exactly what name that should be. ~ Scott (Hopefully the subject change will get us out of the exceptions vs error codes quagmire.)

2 2

[python] AttributeError
by Okko Willeboordse 27 Oct '09

27 Oct '09

Running Boost 1.40 ( Windows server 2003/XP, Visual Studio 2008) Given; #include<boost/python.hpp> struct Foo{ static int bar; }; int Foo::bar=3; BOOST_PYTHON_MODULE(foo){ boost::python::class_<Foo>("Foo",boost::python::init<>()) .def_readonly("bar",Foo::bar); } With Python 2.6.3 and 2.6.4 I get; >c:\Python26\python.exe -c "import foo" Traceback (most recent call last): File "<string>", line 1, in <module> AttributeError: 'Boost.Python.StaticProperty' object attribute '__doc__' is read-only Also; >python Python 2.6.4 (r264:75708, Oct 26 2009, 08:23:19) [MSC v.1500 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or "license" for more information. >>> import foo Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'Boost.Python.StaticProperty' object attribute '__doc__' is read-only >>> import foo >>> dir(foo.Foo) ['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init __', '__instance_size__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr_ _', '__sizeof__', '__str__', '__subclasshook__', '__weakref__'] So importing foo for the second time succeeds but foo.Foo holds no bar With Python < 2.6.3 everything works as expected. See also http://mail.python.org/pipermail/cplusplus-sig/2009-August/014747.html

1 0

[Graph] problem with strong_components.hpp and variant
by Nil Geisweiller 27 Oct '09

27 Oct '09

Hi, it seems there is a conflict between strong_components.hpp and variant, maybe the method boost::get is wrongly overloaded. The problem occurs with 1.40 but not with 1.37, and it is still occurs with the last svn. I attach a minimal code to reproduce the bug + compile error ###### test.cpp ###### //uncomment the line below to get the bug #include <boost/graph/strong_components.hpp> #include <boost/variant.hpp> typedef boost::variant < int, float > intorfloat; int main() { int i(2); intorfloat iof(i); return boost::get<int>(iof); //problem is here } ########### compile error ########### a-lin@a-lin-desktop:~/OpenCog/test/bin$ make [100%] Building CXX object CMakeFiles/test.dir/test.cpp.o In file included from /usr/include/boost/graph/graph_concepts.hpp:17, from /usr/include/boost/graph/depth_first_search.hpp:18, from /usr/include/boost/graph/strong_components.hpp:17, from /home/a-lin/OpenCog/test/test.cpp:2: /usr/include/boost/property_map/property_map.hpp: In instantiation of ‘boost::property_traits<int>’: /usr/include/boost/graph/two_bit_color_map.hpp:46: instantiated from ‘boost::two_bit_color_map<int>’ /home/a-lin/OpenCog/test/test.cpp:10: instantiated from here /usr/include/boost/property_map/property_map.hpp:31: error: ‘int’ is not a class, struct, or union type /usr/include/boost/property_map/property_map.hpp:32: error: ‘int’ is not a class, struct, or union type /usr/include/boost/property_map/property_map.hpp:33: error: ‘int’ is not a class, struct, or union type /usr/include/boost/property_map/property_map.hpp:34: error: ‘int’ is not a class, struct, or union type make[2]: *** [CMakeFiles/test.dir/test.cpp.o] Error 1 make[1]: *** [CMakeFiles/test.dir/all] Error 2 make: *** [all] Error 2 Is it a bug? Thanks a lot! Nil

1 1

[interprocess] mapped_file with wide filename on Windows
by Cory Nelson 27 Oct '09

27 Oct '09

Could the mapped_file constructor allow a wchar_t filename on Windows? Or some cross-platform way to get Unicode support? -- Cory Nelson http://int64.org

2 2

[string]
by remi.chateauneu＠gmx.de 26 Oct '09

26 Oct '09

Hi, Is there any interest for a class for computing Levenshtein and Damerau distances ? It is inspired from http://en.wikipedia.org/wiki/Levenshtein_distance with some enhancements: - The buffer can be reused thanks to a class, avoiding reallocations. - Only one buffer of twice the size of the longest string is necessary (Instead of the product of the size of the two input sequences). (Three times the size for Damerau distance). - It works with any input iterator category for one string, any iterator except input_iterator for the second string. - The distance type is templatized (Allowing to use short ints to save buffer space). - Any type of element can be used (Not only chars). - More efficient than the other implementations I could find on the web, completely inlined (Specific care to maximize memory locality). - The cost function can be specified with a functor (Insertion, deletion, replacement, transposition). - Tested with GCC 3.2.3 and 4.2.3, Visual C++ 2005. There was a proposal for such a function two years ago (edit_distance), but maybe this one, being faster, might be of interest for the string algorithms library ? The code is not very big so please let me attach it here. Thanks /* boost levenshtein.hpp header file * * Copyright Remi Chateauneu 2009 * Distributed under the Boost Software License, Version 1.0. (See * accompanying file LICENSE_1_0.txt or copy at * http://www.boost.org/LICENSE_1_0.txt) * * $Id: $ * * Idea by x */ #ifndef BOOST_LEVENSHTEIN_HPP #define BOOST_LEVENSHTEIN_HPP #include <string.h> #include <vector> namespace boost { /// Given a distance formula, levenshtein or damerau, does some processing of the input parameters. template< class Distance, class Formula > class distance_base { /// This uses Curiously recurring template pattern template < class Iter1, class Iter2 > inline Distance distance_noswap( Iter1 begS1, Iter1 endS1, Iter2 ptrS2, size_t len2 ) { return static_cast< Formula * >(this)->distance_noswap( begS1, endS1, ptrS2, len2 ); }; public: /// If both lengths are available, we can swap to increase speed. template < class Iter1, class Iter2 > Distance distance_swap( Iter1 begS1, Iter1 endS1, size_t len1, Iter2 begS2, Iter2 endS2, size_t len2 ) { /// The longer string should go to the inner loop return ( len1 < len2 ) ? distance_noswap( begS1, endS1, begS2, len2 ) : distance_noswap( begS2, endS2, begS1, len1 ); }; /// For plain containers. We assume that 'size()' has a constant cost. template < class Container1, class Container2 > Distance operator()( const Container1 & s1, const Container2 & s2 ) { return distance_swap( s1.begin(), s1.end(), s1.size(), s2.begin(), s2.end(), s2.size() ); }; /// For plain C-style strings. No need to create a temporary string. Distance operator()( const char * ptrS1, const char * ptrS2 ) { size_t len1 = strlen(ptrS1); size_t len2 = strlen(ptrS2); return distance_swap( ptrS1, ptrS1 + len1, len1, ptrS2, ptrS2 + len2, len2 ); }; /// If no iterator is an input_iterator, we may be able to swap them for performance. template< class Iter1, class Iter2 > Distance distance_iterator( Iter1 beg1, Iter1 end1, std::forward_iterator_tag, Iter2 beg2, Iter2 end2, std::forward_iterator_tag ) { return distance_swap( beg1, end1, std::distance( beg1, end1 ), beg2, end2, std::distance( beg2, end2 ) ); }; /// If the first iterator only is an input_iterator, then process it. template< class Iter1, class Iter2 > Distance distance_iterator( Iter1 beg1, Iter1 end1, std::input_iterator_tag, Iter2 beg2, Iter2 end2, std::forward_iterator_tag ) { return distance_noswap( beg1, end1, beg2, std::distance( beg2, end2 ) ); }; /// If the first iterator only is an input_iterator, then swap them first. template< class Iter1, class Iter2 > Distance distance_iterator( Iter1 beg1, Iter1 end1, std::forward_iterator_tag, Iter2 beg2, Iter2 end2, std::input_iterator_tag ) { return distance_noswap( beg2, end2, beg1, std::distance( beg1, end1 ) ); }; /// According to the type of iterator, not all operations are possible. template< class Iter1, class Iter2 > Distance operator()( Iter1 beg1, Iter1 end1, Iter2 beg2, Iter2 end2 ) { return distance_iterator( beg1, end1, typename std::iterator_traits< Iter1 >::iterator_category(), beg2, end2, typename std::iterator_traits< Iter2 >::iterator_category() ); }; }; // distance_base /// A user functor must have this interface. /// NOTE: The distance must always be positive. template< class Distance, class Char > struct dummy_functor { /// Char subsitution. Distance operator()( Char, Char ) const ; /// Char insertion or deletion. The cost /// is the same for both cases otherwise the distance /// would not be commutative. Distance operator()( Char ) const ; /// Char transposition (Option, for Damerau only). /// This does not depends on the character. Distance operator()(void) const ; }; /// Default functor for the most common case. It is never instantiated. /// Equivalent to a cost of '1' for character insertion, deletion or substitution. struct distance_null_functor {}; /// Specialization for the default case, for performance. /// This wraps a user functor, and compute the core test of Levenshtein distance. template < class Distance, class Functor > class cell_min { /// A user can specify the cost of char insertion, deletion and substitution. /// It must match the interface of dummy_functor. Functor _ftor ; public: cell_min() {}; cell_min( const Functor & refFtor ) : _ftor( refFtor ) {}; /// The cost of character insertion and deletion are the same otherwise /// it would not be commutative, and would not be a distance. template< class Char > Distance min_levenshtein( const Distance & distIJ, const Distance & distI1J, const Distance & distIJ1, const Char & chrLeft, const Char & chrRight ) { return std::min( distIJ + _ftor( chrLeft, chrRight ), std::min( distI1J + _ftor( chrLeft ), distIJ1 + _ftor( chrRight ) ) ); }; /// The operator without argument computes the cost of a transposition /// and does not depend on the transposed characters. /// Damerau is tested on top of Levenshtein comparison. Distance min_damerau( const Distance & prevDiag, const Distance & currDiag ) { return std::min( Distance( prevDiag + _ftor() ), currDiag ); }; }; // cell_min /// Does the core comparison of Levenshtein distance when no /// user functor is provided. This is the most common case /// and must be the fastest. template < class Distance > class cell_min< Distance, distance_null_functor > { public: cell_min() {}; cell_min( const distance_null_functor & ) {}; /// Here we save two additions, than if the general class were used. template< class Char > Distance min_levenshtein( const Distance & distIJ, const Distance & distI1J, const Distance & distIJ1, const Char & , const Char & ) const { return 1 + std::min( distIJ, std::min( distI1J, distIJ1 ) ); }; /// The usual cost of a transposition can be set to 1. /// Damerau is tested on top of Levenshtein comparison. Distance min_damerau( const Distance & prevDiag, const Distance & currDiag ) const { return std::min( prevDiag, currDiag + 1 ); }; }; // cell_min (Specialization) /// Most of times, Distance is 'unsigned int'. template< class Distance > class distance_buffer { /// TODO: Use temporary buffer. std::vector< Distance > _buffer ; size_t _sz ; public: distance_buffer() : _sz(0) {}; void resize( size_t sz ) { if( sz <= _sz ) return ; _buffer.resize( sz ); _sz = _buffer.size(); }; Distance * start(void) { return &_buffer[0]; } }; // distance_buffer /// This wraps a buffer which can be reused, because buffer allocations are costly. /// The distance may be char, short, int: This can reduce the buffer size. /// TODO: Do not resize the buffer but use the stack if less than X elements. /// TODO: Use a specific buffer allocation. template < class Distance = unsigned int, class Functor = distance_null_functor > class levenshtein : public distance_base< Distance, levenshtein< Distance, Functor > > { /// This wraps a user-provided optional functor. cell_min< Distance, Functor > _minFtor ; /// Max size: Twice the longest string + 2. distance_buffer< Distance > _buffer ; public: levenshtein() {}; levenshtein( const Functor & refFtor ) : _minFtor( refFtor ) {}; /// The size of the first range is not needed, any iterator type will do. template < class Iter1, class Iter2 > Distance distance_noswap( Iter1 begS1, Iter1 endS1, Iter2 ptrS2, size_t len2 ) { typedef typename std::iterator_traits< Iter1 >::value_type Char ; /// The buffer contains two lines of distance. _buffer.resize( 2 * ( len2 + 1 ) ); Distance * localPtr = _buffer.start() ; for(unsigned j = 0; j <= len2; ++j) { localPtr[ 2 * j ] = (Distance)j; } const Distance * endPtr = localPtr + 2 * len2 ; /// One cell out of two is associated to one line, the other to the next line. /// The two lines are swapped at each loop. for( unsigned i = 1; ; ) { localPtr = _buffer.start() ; localPtr[1] = Distance(i++) /* i,j+1 */ ; Char chr1 = *begS1++ ; // Restart from the beginning of the second string. for( Iter2 currS2 = ptrS2 ; localPtr != endPtr ; localPtr += 2 ) { const Char chr2 = *currS2++ ; Distance costDiag = localPtr[ 0 ]; /// Optimisation: The distance cannot increase if the chars are identical. if( chr1 != chr2 ) { /// Good data locality in four contiguous cells of the buffer. costDiag = _minFtor.min_levenshtein( costDiag, /* i,j */ localPtr[ 2 ] /* i+1,j */, localPtr[ 1 ] /* i,j+1 */, chr1, chr2 ); } localPtr[ 3 ] = costDiag ; } /// The loop is unrolled two steps by two. if( begS1 == endS1 ) { /// After an even number of half-loops (and lines). return localPtr[ 1 ] /* i+1,j+1 */ ; } /// This starts an odd line. localPtr = _buffer.start() ; localPtr[0] = Distance(i++) /* i,j+1 */ ; chr1 = *begS1++; // Restart from the beginning of the second string. for( Iter2 currS2 = ptrS2 ; localPtr != endPtr ; localPtr += 2 ) { const Char chr2 = *currS2++ ; Distance costDiag = localPtr[ 1 ]; /// Optimisation: The distance cannot increase if the chars are identical. if( chr1 != chr2 ) { /// Good data locality in four contiguous cells of the buffer. costDiag = _minFtor.min_levenshtein( costDiag, /* i,j */ localPtr[ 3 ] /* i+1,j */, localPtr[ 0 ] /* i,j+1 */, chr1, chr2 ); } localPtr[ 2 ] = costDiag ; }; if( begS1 == endS1 ) { /// After an odd number of lines. return localPtr[ 0 ] /* i+1,j+1 */ ; } } /// Should never happen. return Distance(0); }; // distance_noswap }; // levenshtein /// This wraps a buffer which can be reused, because buffer allocations are costly. /// The distance may be char, short, int: This can reduce the buffer size. template < class Distance = unsigned int, class Functor = distance_null_functor > class damerau : public distance_base< Distance, damerau< Distance, Functor > > { /// This wraps a user-provided optional functor. cell_min< Distance, Functor > _minFtor ; /// Max size: Twice the longest string + 2. distance_buffer< Distance > _buffer ; public: damerau() {}; damerau( const Functor & refFtor ) : _minFtor( refFtor ) {}; /// The size of the first range is not needed, any iterator will do. template < class Iter1, class Iter2 > Distance distance_noswap( Iter1 begS1, Iter1 endS1, Iter2 ptrS2, size_t len2 ) { typedef typename std::iterator_traits< Iter1 >::value_type Char ; /// The buffer contains two lines of distance. _buffer.resize( 3 * ( len2 + 3 ) ); Distance * localPtr = _buffer.start() ; for(unsigned j = 0; j <= len2; ++j) { localPtr[ 3 * j] = (Distance)j; } /// One cell out of two is associated to one line, the other to the next line. int offPrev = 2, offCurr = 0, offNext = 1 ; Char chr1, chr1_prev ; /// The three lines are shifted at each loop. for( unsigned i = 1; begS1 != endS1 ; chr1_prev = chr1, ++begS1, ++i, offCurr = offNext, offNext = offPrev, offPrev = offPrev == 2 ? 0 : offPrev + 1 ) { Distance * localPtr = _buffer.start() ; localPtr[offNext] = Distance(i) /* i+1,j */ ; chr1 = *begS1 ; Char chr2, chr2_prev ; Iter2 currS2 = ptrS2 ; for(unsigned j = 0; j < len2; chr2_prev = chr2, ++currS2, ++j, localPtr += 3 ) { chr2 = *currS2 ; Distance costDiag = localPtr[ offCurr ] /* i,j */ ; /// Optimisation: The distance cannot increase if the chars are identical. /// NOTE: Without this test, a valid transposition could not be checked. if( chr1 != chr2 ) { /// Good data locality in four contiguous cells of the buffer. costDiag = _minFtor.min_levenshtein( costDiag, localPtr[ 3 + offCurr ], localPtr[ offNext ], chr1, chr2 ); /// If beyond the first column and line, check for a transposition. /// This makes sense only if the current chars are different. if( ( i > 1 ) && ( j > 0 ) && ( chr1 == chr2_prev ) && ( chr1_prev == chr2 ) ) { costDiag= _minFtor.min_damerau( costDiag, localPtr[ offPrev - 3 ] /* i-1,j-1 */ ); } } localPtr[ 3 + offNext ] = costDiag /* i+1,j+1 */ ; } } return _buffer.start()[ 3 * len2 + offCurr ]; }; // distance_noswap }; // damerau } // namespace boost #endif /* BOOST_LEVENSHTEIN_HPP */ #include <iostream> #include <string> #include <list> #include <vector> #include <iterator> #include "levenshtein.hpp" using namespace std ; /// This can be later used for creating combinations of tests. static void tst_perf(size_t nbLoops) { static const char * tst[] = { "a", "c", "bc", "abc", "bcdef", "abcdegh", "acdeghi", "acedghi", "abcdfgi", "abcfgi", "abcfig" }; const size_t nbTst = sizeof(tst)/sizeof(tst[0]); boost::levenshtein<int> tmpLev ; boost::damerau<int> tmpDam ; while( nbLoops-- ) { for( size_t i = 0 ; i < nbTst ; ++i ) { for( size_t j = i + 1 ; j < nbTst ; ++j ) { int distLev = tmpLev( tst[i], tst[j] ); int distDam = tmpDam( tst[i], tst[j] ); }; }; } } // http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_d… template <class T> size_t edit_distance(const T& s1, const T& s2) { const size_t len1 = s1.size(), len2 = s2.size(); vector<vector<unsigned int> > d(len1 + 1, vector<unsigned int>(len2 + 1)); d[0][0] = 0; for(unsigned int i = 1; i <= len1; ++i) d[i][0] = i; for(unsigned int i = 1; i <= len2; ++i) d[0][i] = i; for(unsigned int i = 1; i <= len1; ++i) for(unsigned int j = 1; j <= len2; ++j) d[i][j] = std::min( std::min(d[i - 1][j] + 1, d[i][j - 1] + 1), d[i - 1][j - 1] + (s1[i - 1] == s2[j - 1] ? 0 : 1) ); return d[len1][len2]; } /// Classical implementation. For comparing results. size_t levenshtein_dist(const std::string & source, const std::string & target) { const size_t n = source.length(); const size_t m = target.length(); if (n == 0) return m; if (m == 0) return n; vector<vector<size_t> > matrix(n + 1, vector<size_t>(m + 1,0)); for (size_t i = 0; i <= n; i++) { matrix[i][0]=i; } for (size_t j = 0; j <= m; j++) { matrix[0][j]=j; } for (size_t i = 1; i <= n; i++) { char s_i = source[i-1]; for (size_t j = 1; j <= m; j++) { char t_j = target[j-1]; int cost; if (s_i == t_j) { cost = 0; } else { cost = 1; } size_t above = matrix[i-1][j]; size_t left = matrix[i][j-1]; size_t diag = matrix[i-1][j-1]; size_t cell = std::min( above + 1, std::min(left + 1, diag + cost)); matrix[i][j]=cell; } } return matrix[n][m]; } /// Classical implementation. For comparing results. size_t damerau_dist(const std::string & source, const std::string & target) { const size_t n = source.length(); const size_t m = target.length(); if (n == 0) return m; if (m == 0) return n; vector<vector<size_t> > matrix(n + 1, vector<size_t>(m + 1,0)); for (size_t i = 0; i <= n; i++) { matrix[i][0]=i; } for (size_t j = 0; j <= m; j++) { matrix[0][j]=j; } for (size_t i = 1; i <= n; i++) { char s_i = source[i-1]; for (size_t j = 1; j <= m; j++) { char t_j = target[j-1]; int cost; if (s_i == t_j) { cost = 0; } else { cost = 1; } size_t above = matrix[i-1][j]; size_t left = matrix[i][j-1]; size_t diag = matrix[i-1][j-1]; size_t cell = std::min( above + 1, std::min(left + 1, diag + cost)); // Step 6A: Cover transposition, in addition to deletion, // insertion and substitution. This step is taken from: // Berghel, Hal ; Roach, David : "An Extension of Ukkonen's // Enhanced Dynamic Programming ASM Algorithm" // (http://www.acm.org/~hlb/publications/asm/asm.html) if( (i > 1) && (j > 1) && (source[i-2] == t_j) && (s_i == target[j-2]) ) { cell = std::min( cell, matrix[i-2][j-2] + 1 ); } matrix[i][j]=cell; } } return matrix[n][m]; } struct TstData { const char * _left ; const char * _right ; unsigned int _lev ; unsigned int _dam ; }; /// We can check whether the result is OK. static const TstData tst_array[] = { { "a","c", 1, 1 }, { "a","bc", 2, 2 }, { "ab","ba", 2, 1 }, { "a","abc", 2, 2 }, { "a","bcdef", 5, 5 }, { "a","abcdegh", 6, 6 }, { "a","acdeghi", 6, 6 }, { "a","acedghi", 6, 6 }, { "a","abcdfgi", 6, 6 }, { "a","abcfgi", 5, 5 }, { "a","abcfig", 5, 5 }, { "c","bc", 1, 1 }, { "c","abc", 2, 2 }, { "c","bcdef", 4, 4 }, { "c","abcdegh", 6, 6 }, { "c","acdeghi", 6, 6 }, { "c","acedghi", 6, 6 }, { "c","abcdfgi", 6, 6 }, { "c","abcfgi", 5, 5 }, { "c","abcfig", 5, 5 }, { "bc","abc", 1, 1 }, { "abcd","badc", 3, 2 }, { "bc","bcdef", 3, 3 }, { "bc","abcdegh", 5, 5 }, { "bc","acdeghi", 6, 6 }, { "bc","acedghi", 6, 6 }, { "bc","abcdfgi", 5, 5 }, { "bc","abcfgi", 4, 4 }, { "bc","abcfig", 4, 4 }, { "abc","bcdef", 4, 4 }, { "abc","abcdegh", 4, 4 }, { "abc","acdeghi", 6, 6 }, { "abc","acedghi", 6, 6 }, { "abc","abcdfgi", 4, 4 }, { "abc","abcfgi", 3, 3 }, { "abc","abcfig", 3, 3 }, { "bcdef","abcdegh", 3, 3 }, { "bcdef","acdeghi", 4, 4 }, { "bcdef","acedghi", 5, 5 }, { "bcdef","abcdfgi", 4, 4 }, { "bcdef","abcfgi", 4, 4 }, { "bcdef","abcfig", 4, 4 }, { "abcdegh","acdeghi", 2, 2 }, { "abcdegh","acedghi", 4, 3 }, { "abcdegh","abcdfgi", 2, 2 }, { "abcdegh","abcfgi", 3, 3 }, { "abcdegh","abcfig", 3, 3 }, { "acdeghi","acedghi", 2, 1 }, { "cadeghi","acedghi", 3, 2 }, { "acdeghi","abcdfgi", 3, 3 }, { "acdeghi","abcfgi", 4, 4 }, { "acdeghi","abcfig", 5, 5 }, { "acedghi","abcdfgi", 4, 4 }, { "acedghi","abcfgi", 4, 4 }, { "acedghi","abcfig", 5, 5 }, { "abcdfgi","abcfgi", 1, 1 }, { "abcdfgi","abcfig", 3, 2 }, { "abcfgi","abcfig", 2, 1 } }; static const size_t nbArr = sizeof(tst_array)/sizeof(tst_array[0]); static boost::levenshtein<int> staticLev ; static boost::damerau<int> staticDam ; /// This is for checking the assembly code generated. static int assembly_levenshtein( const char * a, const char * b ) { return staticLev( a, b ); } static void tst_values(void) { for( size_t i = 0; i < nbArr ; ++i ) { const TstData * p = tst_array + i ; size_t valL = staticLev( p->_left, p->_right ); size_t valD = staticDam( p->_left, p->_right ); size_t edtL = edit_distance( std::string(p->_left), std::string(p->_right) ); size_t oldL = levenshtein_dist( p->_left, p->_right ); size_t oldD = damerau_dist( p->_left, p->_right ); if( ( valL != p->_lev ) || ( oldL != p->_lev ) || ( edtL != p->_lev ) ) { std::cout << "Error L:" << "\tvalL=" << valL << "\tp->lev=" << p->_lev << "\toldL=" << oldL << "\tedtL=" << edtL << "\tp->left=" << p->_left << "\tp->right=" << p->_right << "\n" ; }; if( ( valD != p->_dam ) || ( oldD != p->_dam ) ) { std::cout << "Error D:" << "\tvalD=" << valD << "\tp->dam=" << p->_dam << "\toldD=" << oldD << "\tp->left=" << p->_left << "\tp->right=" << p->_right << "\n" ; }; }; } int main( int argC, const char ** argV ) { tst_values(); if( argC > 1 ) { int nbTst ; sscanf( argV[1], "%d", &nbTst ); tst_perf(nbTst); }; /// So it it not optimized away. std::cout << assembly_levenshtein << "\n" ; }; /// This is for checking the assembly code generated. int assembly_damerau( const char * a, const char * b ) { return staticLev( a, b ); } /// This tests some specific compile-time conditions. template< class Formula > static int compile_formula(Formula refFrm) { std::list< char > chrLst ; vector< char > chrVec ; std::istream_iterator<char> chrStrm ; refFrm( chrLst, chrVec ); refFrm( chrStrm, chrStrm, chrVec.begin(), chrVec.end() ); refFrm( chrLst.begin(), chrLst.end(), chrStrm, chrStrm ); }; struct my_functor { short operator()( char a, char b ) const { return 2 ; }; short operator()( char a ) const { return 1 ; }; short operator()(void) const { return 1 ; }; }; /// This tests some specific compile-time conditions. static int compile_test(void) { boost::levenshtein<int> tmpLev ; compile_formula( tmpLev ); boost::damerau<long long> tmpDam ; compile_formula( tmpDam ); boost::levenshtein<short,my_functor> tmpLevF ; compile_formula( tmpLevF ); my_functor tmpFunc ; boost::damerau<short, my_functor> tmpDamF( tmpFunc ) ; compile_formula( tmpDamF ); };

2 1

boost 1.39 to 1.40 difference: missing toolset and threading tag from library filename?
by Todd Lovette 26 Oct '09

26 Oct '09

Is there a difference in the naming conventions of the libboost_*.so files from boost 1.39 to boost 1.40.0? When I build the boost 1.39 libs they have filenames like... "libboost_thread-gcc44-mt-1_39.so" ..but when I build boost 1.40.0 all the libs filenames are like so... "libboost_thread.so" Did the library naming change in 1.40 or are their new compile options to enable the library naming feature? Build options: (both used on 1.39 & 1.40.0) ------------------------- ./bootstrap.sh --prefix=/usr --libdir=/usr/lib64 ./bjam threading=multi System ------------- Slamd64 12.1(x86_64) using gcc 4.4.2 Any help would be appticiated! Todd :-)

2 2

[test] Errors #including test/floating_point_comparison.hpp
by Emil Dotchevski 26 Oct '09

26 Oct '09

The log below shows a warning and 3 errors in test/predicate_result.hpp from Comeau C++ 4.3.10. Is this easy to fix? (Incidentally, I am not using boost/test, I only need floating_point_comparison.hpp -- shouldn't floating point comparison be independent from boost/test?) Emil Dotchevski Reverge Studios, Inc. http://www.revergestudios.com/reblog/index.php?n=ReCode como-win.compile.c++ ..\..\..\..\..\..\bin\dev\boost-la\libs\la\test\col_matrix_test.test\como-win-4.3.10\debug\link-static\col_matrix_test.obj "C:\code\dev\boost-trunk\boost/test/utils/basic_cstring/basic_cstring.hpp", line 60: warning #68-D: integer conversion resulted in a change of sign enum npos_type { npos = static_cast<size_type>(-1) }; ^ "C:\code\dev\boost-trunk\boost/test/predicate_result.hpp", line 62: warning #54-D: too few arguments in macro invocation BOOST_READONLY_PROPERTY( bool, (predicate_result) ) p_predicate_value; ^ "C:\code\dev\boost-trunk\boost/test/predicate_result.hpp", line 62: error #40: expected an identifier BOOST_READONLY_PROPERTY( bool, (predicate_result) ) p_predicate_value; ^ "C:\code\dev\boost-trunk\boost/test/predicate_result.hpp", line 62: error #277: invalid friend declaration BOOST_READONLY_PROPERTY( bool, (predicate_result) ) p_predicate_value; ^ "C:\code\dev\boost-trunk\boost/test/predicate_result.hpp", line 62: error #65: expected a ";" BOOST_READONLY_PROPERTY( bool, (predicate_result) ) p_predicate_value; ^

1 0

boost policy against inline friend functions?
by Stefan Strasser 26 Oct '09

26 Oct '09

I've noticed boost::shared_ptr and other classes avoid using inline friend functions, e.g. operator < in class shared_ptr scope: public: template<class Y> bool _internal_less(shared_ptr<Y> const & rhs) const { return pn < rhs.pn; } in namespace scope: template<class T, class U> inline bool operator<(shared_ptr<T> const & a, shared_ptr const & b) { return a._internal_less(b); } what's wrong with template<class Y> friend bool operator<(shared_ptr<Y> const & rhs) const { return pn < rhs.pn; } in class shared_ptr? compiler compatibility? other reasons? should boost libraries avoid inline friend functions in general?

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[conversion] Motivation for two NEW generic conver_to and assign_to functions
by vicente.botet 26 Oct '09

26 Oct '09

Hi, I would like to share with you what motivated me to add two new free template functions convert_to<> and assign_to<> on the Boost.Conversion. I've needed recently to convert from boost::chrono::time_point<Clock, Duration> to boost::posix_time::ptime and from boost::chrono::duration<Rep, Period> to boost::posix_time::time_duration. This kind of conversions are needed quite often when you use code from two different libraries that have implemented the same concept using of course different representations and have hard coded the library interface to its own implementation. Well this is a normal situation, we can't avoid. Life is life. Quite often we need to convert unrelated types `Source` and `Target`. As these classes are unrelated, neither of them offers conversion operators to the other. Usually we get it by defining a specific function such as Target ConvertToTarget(Source& v); In my case I started by defining template <typename Rep, typename Period> boost::posix_time::time_duration convert_to_posix_time_time_duration( const boost::chrono::duration<Rep, Period>& from); template <typename Clock, typename Duration> posix_time::ptime convert_to_posix_time_ptime(const chrono::time_point<Clock, Duration>& from); Imagine now that you need to convert a `std::pair<Source, Source>` to a `std::pair<Target, Target>`. The standard defines conversions of pairs if the related types are C++ convertible: template <typename T1, typename T2> struct pair { ... template<class U, class V> //requires Constructible<T1, const U&> && Constructible<T2, const V&> std::pair(const pair<U, V>& p); template<class U , class V> //requires HasAssign<T1, const U&> && HasAssign<T2, const V&> std::pair& operator=(const std::pair& p); ... }; But here the types Target and Source are not convertible other than using a specific function. Well we can again define a specific function std::pair<Target,Target> ConvertToPairOfTarget(std::pair<Source,Source>& v) { return std::make_pair(ConvertToTarget(v.fisrt), ConvertToTarget(v.second)); } While the `ConvertToTarget` could be specific, the `ConvertToPairOfTarget` should be generic template <typename Target1, typename Target2, typename Source1, typename Source2) std::pair<Target1,Target2> ConvertToPair(std::pair<Source1,Source2>& v); In order to do that we need that the pair template parameters define a common function, let it call `convert_to`: template <typename Target, typename Source) Target convert_to(Source& v); Thus `ConvertToPair` can be defined as template <typename Target1, typename Target2, typename Source1, typename Source2) std::pair<Target1,Target2> ConvertToPair(std::pair<Source1,Source2>& v) { return std::make_pair(convert_to<Target1>(v.fisrt), convert_to<Target2>(v.second)); } We need to specialize the `convert_to` function for the specific classes `Source` and `Target`. We can do it as follows template <> Target convert_to<Target, Source>(Source& v) {return ConvertToTarget(v);} In my case I need template <typename Rep, typename Period> boost::posix_time::time_duration convert_to<posix_time_time_duration, boost::chrono::duration<Rep, Period> > (const boost::chrono::duration<Rep, Period>& from) { return convert_to_posix_time_time_duration(from); } template <typename Clock, typename Duration> boost::posix_time::ptime convert_to<posix_time_ptime, chrono::time_point<Clock, Duration> > (const boost::chrono::time_point<Clock, Duration>& from) { return convert_to_posix_time_ptime(from); } So now I can convert std::pair<chrono::time_point<Clock, Duration>, boost::chrono::duration<Rep, Period> > to std::pair<boost::posix_time::ptime, boost::posix_time::time_duration> using the `ConvertToPair` function. What about converting `std::pair<Source,std::pair<Source,Source> >` to `std::pair<Target,std::pair<Target,Target> >`? The issue now is that `convert_to(std::make_pair<to, std::make_pair<to,to> >)` do not compiles because the conversion of `std::pair` is named `ConvertToPair`. So we need to specialize the function `convert_to` for pairs. template <typename T1, typename T2, typename S1, typename S2) static std::pair<T1,T2> convert_to<std::pair<Target1,T2>, std::pair<S1,S2> >( std::pair<Source1,Source2>& from) { { return std::pair<T1,T2>(convert_to<T1>(from.first), convert_to<T2>(from.second)); } There is still a last point. The preceding design works well with unrelated classes, but what about classes that already define some kind of conversion, using a constructor or a conversion operator. Do we need to make specialization for these conversion? The answer is no. We need just to define the default implementation of convert_to function to just return the explicit conversion. template < typename Target, typename Source> Target convert_to(const Source& from) { return Target(from); } With compilers supporting partial specialization of function templates there is no major problem. For the others, we need to use a trick; as it allows partial specialization of classes we can define convert_to by as relying to a specific function of a class, as follows: namespace partial_specialization_workaround { template < typename Target, typename Source > struct convert_to { static Target apply(const Source& val); }; } template < typename Target, typename Source > Target convert_to(const Source& val) { return partial_specialization_workaround::convert_to<Target,Source>::apply(val); } So now we can specialize `partial_specialization_workaround::convert_to` for pairs as follows: namespace partial_specialization_workaround { template <typename Target1, typename Target2, typename Source1, typename Source2) struct convert_to< std::pair<Target1,Target2>, std::pair<Source1,Source2> > { static std::pair<Target1,Target2> apply(std::pair<Source1,Source2>& v) { { return std::pair<T1,T2>(convert_to<T1>(from.first), convert_to<T2>(from.second)); } }; } Conclusion Classes or algorithms relying on a conversion by copy-construction or by the conversion operator can be made more generic by relaying in a function that explicitly states this conversion. Thus, instead of requiring Target(from) require convert_to<Target>(from) The same applies to classes or algorithms relying on the assignment operator. So instead of requiring to = from require assign_to(to, from); The default implementation of assign_to relies on the assignment operator template < typename Target, typename Source > To& assign_to(Target& to, const Source& from) { to = from; return to; } and with the workaround namespace partial_specialization_workaround { template < typename Target, typename Source > struct assign_to { static To& apply(Target& to, const Source& from) { to = from; return to; } }; } template < typename Target, typename Source > To& assign_to(Target& to, const Source& from) { return partial_specialization_workaround::assign_to<Target,Source>::apply(to, from); } For classes that are explicitly convertible and having a self assignment operator it is easy to make a specialization of assign_to as follows. to = convert_to<Target>(from); The rationale is that if there was not a copy constructor from a Source seems reasonable to think that there will not be an assignment operator. So in most of the cases, once we have specialized the convert_to function we recover a reasonable implementation for the assign_to function. When doing multiple assignments we use to do a = b = c; With assign_to we could do assign_to(a, assign_to(b, c)); and if we find this not really readable we can try with tie(a) = tie(b) = c; The behavior of tie recall the tie function of Boost.Tuple, but instead assigning multiple variable at once, assign only one by calling assign_to. So one of the advantages of using this common functions is uniformity. The other is that now we are able to find all the explicit conversions to one type, as we can do with explicit casts. We can even generalize this, so classes or algorithms relying on a member function, can be made more generic by relaying on a free function. The default function implementation could just call to the member function with the equivalent prototype, but this is out of the scope of this library. Note that this is already the case of the free functions as swap(), begin(), next(), end(), ... What about changing the C++ standard? C++1x has added explicit conversion operators, but they must always be defined in the Source class. The same applies to the assignment operator, it must be defined on the Target class. What it will interesting is to be able to add constructors and assignments operators to the class std::pair, so we can say that two pairs are convertible if the parameters are explicitly convertible using a convert_to function template<class U , class V> //requires HasConvertTo<T1, const U&> && HasConvertTo<T2, const V&> std::pair& operator=(const std::pair& p) { return std::make_pair(convert_to<T1>(p.first), convert_to<T1>(p.second)); } But this is not possible. We can not add operators to a class from outside. A more generic alternative could be to make an evolution to the standard, so the convertible concept takes car of extrinsic conversions. We could be able to implicitly or explicitly add extrinsic conversion operators between unrelated types. Assignment operators could also be specialized. template < typename To, typename From > operator To(const From& val); template < typename To, typename From > To& operator=(To& to, const From& from); For example we could specialize the conversion from as chrono::time_point<Clock, Duration> to posix_time::ptime follows template < class Clock, class Duration> operator boost::posix_time::ptime(const boost::chrono::time_point<Clock, Duration>& from) { typedef boost::chrono::time_point<Clock, Duration> time_point_t; typedef boost::chrono::nanoseconds duration_t; typedef boost::duration_t::rep rep_t; rep_t d = boost::chrono::duration_cast<duration_t>(from.time_since_epoch()).count(); rep_t sec = d/1000000000; rep_t nsec = d%1000000000; return boost::posix_time::from_time_t(0)+ boost::posix_time::seconds(static_cast<long>(sec))+ boost::posix_time::nanoseconds(nsec); } The convert_to and the assign_to functions preted to be a library solution to the convertibility of unrelated types problem. Best regards, _____________________ Vicente Juan Botet Escribá

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[rfc] a library for gesture recognition, speech recognition, and synthesis
by Stjepan Rajko 26 Oct '09

26 Oct '09

Hello, For the past few years I've been working on the AME Patterns library - a generic library for modeling, recognition and synthesis of sequential patterns. So far it's been applied mostly to gesture recognition (e.g., recognition of mouse gestures, full body gestures from video or motion capture data, accelerometer gestures), but recently it has also shown some good results on speech datasets. It can also be used to synthesize the same kinds of patterns it can recognize (e.g., you could use it to synthesize a gesture or speech, or purely numerical patterns). The library provides support for hidden Markov models and other related models. The design is concept-based, and the library uses the Boost Graph Library, Boost.Range (including the RangeEx extension), Boost.Fusion, Boost.Math, Boost.Random, and other boost libraries. The documentation for the library is available here: http://ame4.hc.asu.edu/amelia/patterns/ However, the documentation is lacking, so I'm curious to know which parts of the functionality (if any) are of interest to the boost community, so I know what parts of the documentation to focus on. I am also considering proposing a presentation of this library to BoostCon. The library is currently released under the GPL, which I realize is not acceptable to some. Please let me know your thoughts. If anyone is interested in using this library, please let me know what you'd like to use it for and I'd be happy to help you get started. Kind regards, Stjepan

2 3

[conversion] How to repere assignement to a variable? (was [property] interest in C# like properties for C++?)
by vicente.botet 26 Oct '09

26 Oct '09

Hi, in the thread about C# like properties we were talking about the advantage to be able to repere assignation to properties. I said that, another way to repare the assignments is to use a free function assign_to, like we use the free function swap, or the cast family functions. assign_to(a.p_X, 1); assign_to call by default the assignment operator. If we want transitive assignation a = b = c; we could do assign_to(a, assign_to(b, c)); and if we find this not really readable we can try with tie(a) = tie(b) = c; tie is a template function returning an ca_wrapper. template <typename T> ca_wrapper <T> tie(T& r) { return ca_wrapper<T>(r); } ca_wrapper is responsable to transforming the assignation and operator conversion on a call to assign_to and no more. template <typename T> class ca_wrapper { T& ref_; public: ca_wrapper(T& r) : ref_(r) {} template <typename U> T& operator =(U const& u) { return assign_to(ref_, u); } template <typename U> operator U() { return convert_to(ref_, u); } }; The advantage of having a specific function is that we can specialize the assign_to function for unrelated classes. The Boost.Conversion library (on the review schedule) defines two free functions convert_to and assign_to which by default use the conversion operator and the assignment. We can see convert_to as a getter and assign_to as a setter. The major advantage is that with a uniform syntax, the user can however specialize them to do conversion and assignations between unrelated types. I don't know if tie is a good name to manage with assignation of a variable, I have taken the name from the Boost.Tuple? Regards, _____________________ Vicente Juan Botet Escribá P.S. tie and ca_wrapper are new features of Boost.Conversion v.0.3

2 3

boost design details
by wildinto wildinto 26 Oct '09

26 Oct '09

hi all, because i'm studying the generic programming, i just want to study boost to get the most useful skills, but i can't find any design details about boost. such as boost bind, so, anyone who can tell where i can find the design details about the design of each boost lib ? thanks very much! best regards, Thunder

1 0

[BGL] [Property Map] PropertyGraph concept
by Cosimo Calabrese 26 Oct '09

26 Oct '09

Hi to all, I've taked a look to the PropertyGraph concept, and it defines the following valid expression: get(p, g, x) and its return type: boost::property_traits<Map>::*value_type* Also the docs of Property Map library says that the get() function return the property *by value*, making a copy of the property. But looking to the \boost\graph\detail\adjacency_list.hpp file, I've noticed that the return value of the get function is: typename boost::property_traits< typename boost::property_map<typename Config::graph_type, Property>::type >::*reference* Why this difference? Or they are the same think? Which is the correct specific? Thanks in advance, Cosimo Calabrese.

2 1

[RegEx] Performance degradation since 1.36
by Dave Vest 26 Oct '09

26 Oct '09

I've just downloaded boost 1.40, compiled the libraries, and re-compiled our application. Part of our application uses regular expressions extensively to search through source code and the performance appears to be up to 5 x slower in release mode than with the 1.36 libraries. Boost source (no modifications) compiled with Visual Studio 2008 on Win 7. (Note: 1.36 was compiled with VS 2008 on Win Vista.) bjam debug release --with-thread --with-regex --with-date_time link=static Regex creation: boost::regex::flag_type flags = boost::regex::perl | boost::regex::optimize | boost::regex::icase); boost::regex * pengine = new boost::regex(strSampleExpression, flags); .. Regex use: boost::regex_iterator<char const*> itMatch(pszStr, pszStr + nStrLen, *pengine); boost::regex_iterator<char const*> itEnd; if ( itMatch != itEnd ) { . } A simple for(int i=0;i<100000;++i) loop test shows huge differences. Any ideas why 1.40 is so much slower? Some change in default traits or some documentation note I've missed?

1 0

[PBGL] Distributed BFS example : input and outpu
by Sandeep Gupta 26 Oct '09

26 Oct '09

Hello, I am trying to understand how the example libs/graph_parallel/example/breadth_first_search.cpp works. I am not able to understand (neither find any documentation for it) the input and output of the program. To the best of my understanding a valid input to this program is graph/test/ weighted_graph.gr. What's the format for the input. And why does the output of BFS dependent upon the number of process in the mpirun argument. Would greatly appreciate any explanation or relevant pointers. -thanks Sandeep

1 0

[Test] Building with Comeau C/C++ 4.3.10.1 fails
by Mateusz Loskot 25 Oct '09

25 Oct '09

Hi, Where can I find current status what Boost libraries compile using Comeau C/C++ compiler? I've tried to build Boost.Test and it fails. Is this a known issue? Should I submit a ticket with detailed errors log? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

2 3

tuple<T,T,...> generator meta-function
by Emre Turkay 23 Oct '09

23 Oct '09

Hi folks, How can I do this in a better way? template <typename T, size_t N> struct make_tuple { }; template <typename T> struct make_tuple<T, 1> { typedef boost::tuple<T> type; }; template <typename T> struct make_tuple<T, 2> { typedef boost::tuple<T, T> type; }; template <typename T> struct make_tuple<T, 3> { typedef boost::tuple<T, T, T> type; }; template <typename T> struct make_tuple<T, 4> { typedef boost::tuple<T, T, T, T> type; }; // ... Thanks, emre

4 3

Re: [boost] [property] interest in C# like properties for C++?
by Stefan Strasser 23 Oct '09

23 Oct '09

Not trying to beat a dead horse, but this is yet another reason to keep the parenthesis syntax: name().size() -- Ursprüngl. Mitteil. -- Betreff: Re: [boost] [property] interest in C# like properties for C++? Von: Olaf van der Spek <olafvdspek(a)gmail.com> Datum: 23.10.2009 07:44 On Fri, Oct 23, 2009 at 1:30 AM, Edward Diener <eldiener(a)tropicsoft.com> wrote: > Of course you can support reference properties along with value properties. > It is just very hard, if not impossible, to support both kinds using the > same template class. So really one would not a separate template class to > support reference properties. Maybe I should've said class reference. Take std::string for example. I'd be very interested if you've got code that supports for example name.size() where name is your reference property class. name->size() is no problem, but I'd like to have name.size(). Olaf _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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[random] seeding with arbitrary integers
by Steven Watanabe 23 Oct '09

23 Oct '09

AMDG Currently, some PRNGs cannot be seeded with certain values. For example, the seed for linear_congruential cannot be a multiple of the modulus if the offset is zero. lagged_fibonacci also cannot be seeded with 0, because it uses minstd_rand0. Since linear_congruential already tries to wrap the seed to fit in the range, I'd like to change it so that any seed works. The other generator that needs to be changed is linear_feedback_shift. linear_feedback_shift cannot be seeded with a small integer. What I've done is to add the minimum value to the seed, if the seed is too small. I'm not sure that this is a good solution, since this means that there are a few (and only a few) seeds that result in identical generators. Thoughts? Would it be better to wrap the values to make them fit in range instead? At least this would be consistent with linear_congruential. I've attached a patch with these changes and test cases. See also: http://svn.boost.org/trac/boost/ticket/3516 which prompted this investigation. In Christ, Steven Watanabe

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[asio] help windows.h not littering namespace
by Bjoern Thiel 23 Oct '09

23 Oct '09

Hallo, in socket_types.hpp instead of ... # if defined(__CYGWIN__) # if !defined(__USE_W32_SOCKETS) # error You must add -D__USE_W32_SOCKETS to your compiler options. # endif // !defined(__USE_W32_SOCKETS) # if !defined(NOMINMAX) # define NOMINMAX 1 # endif // !defined(NOMINMAX) # endif // defined(__CYGWIN__) # include <winsock2.h> ... I suggest something like ... # if defined(__CYGWIN__) # if !defined(__USE_W32_SOCKETS) # error You must add -D__USE_W32_SOCKETS to your compiler options. # endif // !defined(__USE_W32_SOCKETS) # endif // defined(__CYGWIN__) # if !defined(NOMINMAX) # define NOMINMAX 1 # define BOOST_NOMINMAX_DEFINED 1 # endif // !defined(NOMINMAX) # include <winsock2.h> # if defined(BOOST_NOMINMAX_DEFINED) # undef NOMINMAX # undef BOOST_NOMINMAX_DEFINED # endif // defined(BOOST_NOMINMAX_DEFINED) ... Thanks. Bjoern Thiel

1 0

[libboost_regex-1_32.dylib] Validating Email address using Regx failing in boost
by Arun 23 Oct '09

23 Oct '09

Hi All, I am using boost regex libraries (libboost_regex-1_32.dylib) for validation of strings. The regular expression string i use is as below. string expr = "^((?>[a-zA-Z\\d!#$%&'*+\\-/=?^_`{|}~]+\\x20*|\"((?=[\\x01-\\x7f])[^\"\\\\]|\\\\[\\x01-\\x7f])*\"\\x20*)*(?<angle><))?((?!\\.)(?>\\.?[a-zA-Z\\d!#$%&'*+\\-/=?^_`{|}~]+)+|\"((?=[\\x01-\\x7f])[^\"\\\\]|\\\\[\\x01-\\x7f])*\")@(((?!-)[a-zA-Z\\d\\-]+(?<!-)\\.)+[a-zA-Z]{2,}|\\[(((?(?<!\\[)\\.)(25[0-5]|2[0-4]\\d|[01]?\\d?\\d)){4}|[a-zA-Z\\d\\-]*[a-zA-Z\\d]:((?=[\\x01-\\x7f])[^\\\\\\[\\]]|\\\\[\\x01-\\x7f])+)\\])(?(angle)>)$"; When i make a call boost::regex regExpr(expr); it is throwing what(): Invalid preceding regular expression. I got the regular expression from http://regexlib.com/REDetails.aspx?regexp_id=711 and converted into std::string. If i print the string onto a terminal, the string exactly matches with the regular expression ^((?>[a-zA-Z\d!#$%&'*+\-/=?^_`{|}~]+\x20*|"((?=[\x01-\x7f])[^"\\]|\\[\x01-\x7f])*"\x20*)*(?<angle><))?((?!\.)(?>\.?[a-zA-Z\d!#$%&'*+\-/=?^_`{|}~]+)+|"((?=[\x01-\x7f])[^"\\]|\\[\x01-\x7f])*")@(((?!-)[a-zA-Z\d\-]+(?<!-)\.)+[a-zA-Z]{2,}|\[(((?(?<!\[)\.)(25[0-5]|2[0-4]\d|[01]?\d?\d)){4}|[a-zA-Z\d\-]*[a-zA-Z\d]:((?=[\x01-\x7f])[^\\\[\]]|\\[\x01-\x7f])+)\])(?(angle)>)$ I am not able to find why boost is telling the string as invalid regular expression. I work in Mac OS X Leopard, and use boost_1_32. Any ideas? Thanks Arun Reply Forward New window Print all « Back to Sent Mail Archive Report spam Delete Move to Inbox Labels More actions 1 of 598 Older › Use free POP access to download your messages to Outlook or devices that support POP. Learn more You are currently using 1306 MB (17%) of your 7382 MB. Last account activity: 9 minutes ago at this IP (125.16.133.35). Details Gmail view: standard | turn off chat | older version | basic HTML Learn more ©2009 Google - Terms - Privacy Policy - Google Home

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[asio] icmp example not working on Windows 2000
by Wolfgang Fertsak 23 Oct '09

23 Oct '09

Hello! The icmp example provided with the asio-library in 1.40 throws a system error with code 10044 "The support for the specified socket type does not exist in this address family." when compiled with _WIN32_WINNT 0x0500 and executed on an Win2000 machine. The error comes from the gai_echeck()-function in socket_ops.hpp which is called with family AF_INET and socktype SOCK_RAW: inline int gai_echeck(const char* host, const char* service, int flags, int family, int socktype, int protocol) { .... switch (family) { case AF_UNSPEC: break; case AF_INET: case AF_INET6: if (socktype != 0 && socktype != SOCK_STREAM && socktype != SOCK_DGRAM) return EAI_SOCKTYPE; ... I have attached the callstack for call to gai_echeck() I'm using Visual Studio 2005 and boost 1.39 (although the example is from boost 1.40) I changed the return value of gai_echeck() back to 0 in the debugger and then the rest of the icmp(ping) example ran without any apparent problems. Best regards, Wolfgang boost::asio::detail::socket_ops::gai_echeck(const char * host=0x0012fad0, const char * service=0x0012faa8, int flags=0, int family=2, int socktype=3, int protocol=1) Line 1380 C++ boost::asio::detail::socket_ops::getaddrinfo_emulation(const char * host=0x0012fad0, const char * service=0x0012faa8, const addrinfo * hintsp=0x0012fa78, addrinfo * * result=0x0012faf0) Line 1441 + 0x1d bytes C++ boost::asio::detail::socket_ops::WspiapiGetAddrInfo(const char * host=0x0012fad0, const char * service=0x0012faa8, const addrinfo * hints=0x0012fa78, addrinfo * * result=0x0012faf0, boost::system::error_code & ec={...}) Line 1801 + 0x15 bytes C++ boost::asio::detail::resolver_service<boost::asio::ip::icmp>::resolve(boost::shared_ptr<void> & __formal={...}, const boost::asio::ip::basic_resolver_query<boost::asio::ip::icmp> & query={...}, boost::system::error_code & ec={...}) Line 147 + 0x51 bytes C++ boost::asio::ip::resolver_service<boost::asio::ip::icmp>::resolve(boost::shared_ptr<void> & impl={...}, const boost::asio::ip::basic_resolver_query<boost::asio::ip::icmp> & query={...}, boost::system::error_code & ec={...}) Line 105 + 0x1b bytes C++ boost::asio::ip::basic_resolver<boost::asio::ip::icmp,boost::asio::ip::resolver_service<boost::asio::ip::icmp> >::resolve(const boost::asio::ip::basic_resolver_query<boost::asio::ip::icmp> & q={...}) Line 98 + 0x1d bytes C++ pinger::pinger(boost::asio::io_service & io_service={...}, const char * destination=0x00324199) Line 32 + 0x1a bytes C++ main(int argc=2, char * * argv=0x00324170) Line 155 + 0x16 bytes C++

1 0

boost-test and Mac 10.6
by Mike Tegtmeyer 23 Oct '09

23 Oct '09

Does anyone know anything about boost test crashing on Mac 10.6? Unless I'm missing something, it is completely broken for 1.40 and trunk. There is a Ticket #2889 (closed Bugs: fixed) for malloc errors that looks awfully similar to what I'm seeing. file is: rotor:~ tegtmeye$ cat boost_test.cc #define BOOST_TEST_MODULE footest test #include <boost/test/unit_test.hpp> BOOST_AUTO_TEST_CASE( test1 ) { BOOST_CHECK( true ); } BOOST_AUTO_TEST_CASE( test2 ) { BOOST_CHECK( true ); } BOOST_AUTO_TEST_CASE( test3 ) { BOOST_CHECK( true ); } BOOST_AUTO_TEST_CASE( test4 ) { BOOST_CHECK( true ); } rotor:~ tegtmeye$ g++ boost_test.cc /usr/local/lib/libboost_unit_test_framework.a rotor:~ tegtmeye$ ./a.out Running 4 test cases... *** No errors detected a.out(69716) malloc: *** error for object 0x30001002002e0: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug Abort trap

3 3

[intrusive] rtti_base class proposition
by Ireneusz Szpilewski 22 Oct '09

22 Oct '09

Hi, Here is my idea for this little class: class rtti_base { virtual void _dummy() {} }; Every class deriving from rtti_base can be queried by means of RTTI, in particular rtti_base class and dynamic_cast can be used in similar way as IUnknown and QueryInterface() in COM Object Model rtti_base* could be used as a "smart" void* pointer - we can get type information, and use it in heterogenic containers as in: std::list<rtti_base*> beings; we can iterate through beings and call Cat::GiveMilk() for cats but Girl::Kiss() for girls. :-) The main purpose of this class is to set some standard name for that pointer type. Ireneusz Szpilewski

7 27

Re: [boost] linking on OSX
by David M. Cotter 22 Oct '09

22 Oct '09

>> please be explicit, are you saying i should type exactly this: >> >> ./bjam macosx-version-min=10.4 architecture=combined >> linkflags="-Wl,-force_cpusubtype_ALL" --with-thread -a -n install > > I don't know how to use bjam, nor do I have any wish to learn, so I > can't help you with its command line arguments. > Did doing that give you -Wl,-force_cpusubtype_ALL for the g++ > command that creates libboost_thread.dylib? apparently the extra -Wl is not necessary, since when i leave it off, it still gets sent, probably due to the macosx-min-version flag. WITH: > ./bjam macosx-version-min=10.4 architecture=combined linkflags="-Wl -force_cpusubtype_ALL" --with-thread -a -n install "g++" -dynamiclib -Wl,-single_module -install_name "libboost_thread.dylib" -o "bin.v2/libs/thread/build/darwin-4.2.1/ release/architecture-combined/macosx-version-min-10.4/threading-multi/ libboost_thread.dylib" "bin.v2/libs/thread/build/darwin-4.2.1/release/ architecture-combined/macosx-version-min-10.4/threading-multi/pthread/ thread.o" "bin.v2/libs/thread/build/darwin-4.2.1/release/architecture- combined/macosx-version-min-10.4/threading-multi/pthread/exceptions.o" "bin.v2/libs/thread/build/darwin-4.2.1/release/architecture-combined/ macosx-version-min-10.4/threading-multi/pthread/once.o" - headerpad_max_install_names -mmacosx-version-min=10.4 -Wl,-dead_strip - no_dead_strip_inits_and_terms -arch i386 -arch ppc -Wl - force_cpusubtype_ALL note: see it's in there TWICE? is the problem that i'm missing a comma? WITHOUT: > ./bjam macosx-version-min=10.4 architecture=combined linkflags="- force_cpusubtype_ALL" --with-thread -a -n install "g++" -dynamiclib -Wl,-single_module -install_name "libboost_thread.dylib" -o "bin.v2/libs/thread/build/darwin-4.2.1/ release/architecture-combined/macosx-version-min-10.4/threading-multi/ libboost_thread.dylib" "bin.v2/libs/thread/build/darwin-4.2.1/release/ architecture-combined/macosx-version-min-10.4/threading-multi/pthread/ thread.o" "bin.v2/libs/thread/build/darwin-4.2.1/release/architecture- combined/macosx-version-min-10.4/threading-multi/pthread/exceptions.o" "bin.v2/libs/thread/build/darwin-4.2.1/release/architecture-combined/ macosx-version-min-10.4/threading-multi/pthread/once.o" - headerpad_max_install_names -mmacosx-version-min=10.4 -Wl,-dead_strip - no_dead_strip_inits_and_terms -arch i386 -arch ppc -force_cpusubtype_ALL

2 3

[conversion] Release v0.3 : Changing the order of assign_to parameters + `tie' function
by vicente.botet 22 Oct '09

22 Oct '09

Hi, I have just released the version 0.3 of Boost.Conversion , which includes since my last publicly announced version 0.1: Version 0.3.0, Oct 22, 2009 Changing the order of to and from parameters on assign_to + Added `tie' function Incopatibility: * Changing the order of to and from parameters on assign_to. * Now boost/conversion/convert_to.hpp and boost/conversion/assign_to.hpp files are separated. New Features: * Added <boost/conversion.hpp> global file. * Added mca() function. * Added convert_to_via function. Test: * Added test for the new features Version 0.2.0, Mai 16, 2009 Adding array + fusion::tuples + Adaptation to Boost 1.39 New Features: * conversion between boost::array of explicitly convertible types. * conversion between Boost.Fusion sequences of explicitly convertible types. You can found all the detail for dowloading, documentation, ... in http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction#Boost.Conve… I'd appreciate it if people could take a look, test it on their compiler and give me some feedback. Best regards, _____________________ Vicente Juan Botet Escribá

1 0

Re: [boost] linking on OSX
by David M. Cotter 21 Oct '09

21 Oct '09

please be explicit, are you saying i should type exactly this: ./bjam macosx-version-min=10.4 architecture=combined linkflags="-Wl,- force_cpusubtype_ALL" --with-thread -a -n install cuz that didn't do anything On Oct 21, 2009, at 11:03 AM, Peter O'Gorman wrote: > On 10/21/2009 12:26 PM, David M. Cotter wrote: >> you can see that the build system is in fact emitting the correct >> command for linking, however it is apparently being ignored on PPC > >> >> malkier:lib davec$ otool -f -v ./libboost_thread.dylib >> Fat headers >> fat_magic FAT_MAGIC > >> architecture *ppc7400* >> cputype CPU_TYPE_POWERPC >> cpusubtype *CPU_SUBTYPE_POWERPC_7400* >> capabilities 0x0 > >> >> so i'm dead in the water on this project. any insight or help that >> solves this would win you free mac Karaoke software. :) and my >> gratitude. >> > > Change it to -Wl,-force_cpusubtype_ALL, the flag is not passed along > by gcc to the linker. > > If you build all your object files with the -mmacosx-version-min > flag, as far as I know, you shouldn't be getting ppc7400 in the > cpusubtype. > > Peter > -- > Peter O'Gorman > http://pogma.com

2 2

[BGL] Multithread problem inserting edges and exploring the same graph
by Cosimo Calabrese 21 Oct '09

21 Oct '09

Hi to all, I've a problem on BGL. My environment is WinXP, Visual Studio 2005, Boost 1.37. I'm trying to use BGL in the following way. I've a single graph in my application, that is an adjacency_list< vecS, vecS, ... >, and I've 2 kind of threads that work on the graph: - some "Explorer" threads, that executes a Dijkstra's algorithm repeatedly; - some "Integrator" thread, that call the add_edge() function repeatedly. The program often crashes, because it cannot dereference some graph elements, some auto_ptr... The crash isn't sistematic, so I think there's a concurrency problem. I think that the problem is in the use of the vectors in the implementation of the graph. In general, if I've an iterator 'it' that point on an vector's element A, and I insert another element B before A, then the iterator is now invalid. I suppose that it happens something of similar in the graph. If I read the out-edge list of a vertex at the same time that I add another out-edge to the same vertex, the reading may be inconsistent. So I've tried with an adjacency_list< listS, vecS, ... >, because if I add an element to a list, the previous reference are still valid, but I've experienced the same problem again. If what I've said is correct, then I think that with an adjacency_matrix I will not have problems, but I've approximately 5 millions of vertices, and the graph is sparse. I think that is a waste of memory. And what about the exploring time? Another question: if I launch *only* a set of Explorer thread, it seems that there aren't problems with EdgeList = listS and EdgeList = vecS too. Can someone confirm to me that the exploring algorithms, like Dijkstra, don't modify the graph structure? Are they read-only algorithms? Can I safely launch multiple exploration threads simultaneously? Can someone help me? Many thanks in advance, Cosimo Calabrese.

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Re: [boost] Preliminary submission: generic linear algebra algorithms library Boost LA
by Daniel Pfeifer 21 Oct '09

21 Oct '09

Hi Emil, I had a look at the documentation and examples of your library and I think it is awesome so far. Your library could be a C++ complement to the builtin vector and matrix types and functions of GLSLang. (see http://www.opengl.org/registry/doc/GLSLangSpec.1.50.09.pdf pages: 23, 53ff, 60, 81ff). Since you already have mastered swizzling, implementing the rest should be peanuts. My wishlist: * component wise multiplication and division of two vectors implemented as operators (as in GLSL). * all the vector and matrix related functions described in chapter 8 of the GLSL spec. * operator[] As for the name: If LA is too misleading, I would propose "kd-math" or "math-kd". There already is another project called math3d, and since your library is not limited to three dimensions, kd (as in kd-tree) suits quite well in my opinion. cheers, Daniel Emil Dotchevski wrote: > I remember some past discussions on this mailing list about the need > for similar library in Boost, so I hope it is OK to skip the interest > query and request a preliminary review for Boost LA. > > Boost LA provides a set of generic linear algebra algorithms, > primarily for working with vectors and matrices of static size. The > library also defines vector and matrix data types, however it allows > users to introduce their own types by specializing the vector_traits > and matrix_traits templates. > > Documentation and source code available at > http://www.revergestudios.com/boost-la, released under the Boost > Software License. > > Thanks, > Emil Dotchevski > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

2 1

Re: [boost] linking on OSX
by David M. Cotter 21 Oct '09

21 Oct '09

okay i've stared at the doc for bjam but can find NOTHING which indicates how to tell it to build for 10.4 anyone have an idea on that? >>> This load command (see mach-o/loader.h) is LC_DYLD_INFO_ONLY. >>> >>> I can only guess, but did you compile boost with -mmacosx-version- >>> min=10.6, but built your app with an earlier deployment target, >>> and when you attempt to run it, you're doing so on Leopard? >> >> i did not specify a min version when i built. so what should i >> do? this is what i suspect: >> >> re-build boost using -mmacosx-version-min=10.4 >> >> and all will be well? > > Should work, though I don't know if you'll also have to point boost > at the 10.4 SDK with -isysroot. I suspect not.

4 17

BOOST_FOREACH like macro for map
by mobi phil 21 Oct '09

21 Oct '09

Hello, new to this list... did not find anything similar on net. One of the annoyances with std::map is that if you work with const maps, then there is no "one line" code to get an element knowing the key. given the map const map<string, string> aStringMap; I cannot write const string &s = aStringMap["key"]; process(s); I should write: map<string, string>::const_iterator it=aStringMap.find("key") if( it != aStringMap.end() ) { process(it->second) } so would be nice to have a macro like BOOST_CONSTMAPFIND(aStringMap, "key", data) { processResult( data ); } the version if(BOOST_CONSTMAPFIND(l_map, l_key, l_data) ) { } Seems to be impossible to implement -- rgrds, mobi phil being mobile, but including technology http://mobiphil.com

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Re: [boost] linking on OSX
by David M. Cotter 21 Oct '09

21 Oct '09

okay we now know what the problem is, the question for the BOOST folk is: how do i do this with bjam? On Oct 20, 2009, at 7:23 PM, Chris Suter wrote: > Hi David, > > On Wed, Oct 21, 2009 at 1:03 PM, David M. Cotter <me(a)davecotter.com> > wrote: > okay. everything is working fantastically, however, it won't run on > G3 machine running 10.4.11 > it works perfectly on a G4 PPC machine also running 10.4.11 > > is there some way to "tune" bjam to emit G3-compatible code? > cuz i'm getting this: > > Host Name: TAZ-2 > Date/Time: 2009-10-20 05:56:18.099 -0700 > OS Version: 10.4.11 (Build 8S165) > Report Version: 4 > > Command: FooBar Pro > Path: /Applications/FooBar Pro.app/Contents/MacOS/FooBar Pro > Parent: WindowServer [310] > > Version: FooBar Pro 1.0d50r33 (1.0) > > PID: 445 > Thread: Unknown > > Link (dyld) error: > > Library not loaded: @loader_path/../SharedSupport/ > libboost_thread.dylib > Referenced from: /Applications/FooBar Pro.app/Contents/MacOS/ > FooBar Pro > Reason: no suitable image found. Did find: > /Applications/FooBar Pro.app/Contents/MacOS/../SharedSupport/ > libboost_thread.dylib: no matching architecture in universal wrapper > /Applications/FooBar Pro.app/Contents/MacOS/../SharedSupport/ > libboost_thread.dylib: no matching architecture in universal wrapper > > This is most likely because you're only building for G4 machines and > greater. If you run otool -f -v <binary>, you'll probably see > cpusubtype set to CPU_SUBTYPE_POWERPC_7400 (which basically means G4 > or greater). > > To fix, as a minimum, you need to make sure that your deployment > target is set to 10.4 or less and make sure your architecture > setting is ppc rather than ppc7400. > > Kind regards, > > Chris

1 0

[interprocess] new problem with move-aware containers
by Thorsten Ottosen 20 Oct '09

20 Oct '09

Hi Ion, I'm using the boost::interprocess::multiset from trunk with vc9. After updating, some of my code stopped working. I use a set like multiset<const Node*,SomePredicate> and when calling set.insert( &obj ) I get compile errors. Specifically in interprocess\detail\move.hpp(79) I don't understand the details of these move-emulation tricks, but the compiler complains that T=U* for some U is not a legal base class. AFAICT, the compiler is right: template <class T> class rv : public T { rv(); ~rv(); rv(rv const&); void operator=(rv const&); }; -Thorsten

2 1

bzip with spreadsort
by Steven Ross 20 Oct '09

20 Oct '09

I've added fasterbzip2-1.0.5.zip to the Boost Vault as an example application of the Spreadsort hybrid radix sorting algorithm. As bzip is written in C, I couldn't use the template library directly and had to modify the source. Using the Spreadsort algorithm causes a measurable speed improvement on Windows for the first 100MB of wikipedia from: http://cs.fit.edu/~mmahoney/compression/textdata.html<http://cs.fit.edu/%7Emmahoney/compression/textdata.html> along with other data I tested. Please note that bzip doesn't spend all its time compressing, already has two stages of radix sort, and has specialized and manually inlined comparison functions, so it's heavily optimized to begin with and improvements are minor.

1 0

[mpl] Is there anyone working on mpl with variadic templates ?
by luozhiyuan 20 Oct '09

20 Oct '09

Is it possible that BOOST_MPL_LIMIT_/seq/_SIZE can be removed when we have variadic templates ?

2 1

[bitfield] Pre-review request
by vicente.botet 19 Oct '09

19 Oct '09

Hi all, I have adapted the Boost.Bitfield library from Emile Cormier with its permision and I have requested the Review Wizards to include Boost.Bitfield on the review schedule. The library is now quite stable. Even if there were not too much interest in the Boost ML, only 140 dowloads from the Boost Vault, the version on which it is based had more that 1500 downloads, so I suppose that the subject interest a lot of people. I really think Boost.Bitfield is the complement the Boost.Endian library to manage with all the endian issue, allowing to mange not only endian interger issues, but also endian bitfield issues. I hope that including it on the review schedule will generate more interest and help me to improve the library. I would appreciate it if people could participate to this Pre-review, reading the documentation, testing on their compiler, .... Every comment is wellcome. BTW, I'm looking for a review manager. Thanks for all, Vicente Boost.Bitfield Author(s): Vicente J. Botet Escribá, Emile Cormier Download: `Boost Vault: <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bitfie…> Boost Sandbox: https://svn.boost.org/svn/boost/sandbox/bitfield Documentation: https://svn.boost.org/svn/boost/sandbox/bitfield/libs/bitfield/doc/index.ht… Html doc also included the Vault package Categories: Portability, Integer Description: Portable bitfields traits. Boost.Bitfield consists of: * a generic bitfield traits class providing generic getter and setter methods. * a BOOST_BITFIELD_DCL macro making easier the definition of the bitfield traits and the bitfield getter and setter functions. Example declaration: struct Rgb565 { uint16_t storage; BOOST_BITFIELD_DCL(uint16_t, storage, unsigned char, red, 0, 4); BOOST_BITFIELD_DCL(uint16_t, storage, unsigned char, green, 5, 10); BOOST_BITFIELD_DCL(uint16_t, storage, unsigned char, blue, 11,15); }; Example usage: Rgb565 r; r.storage= 0xffff; // Write to a bitfield. Note that parenthesis are needed around the bitfield r.red() = 23; // Read from a bitfield unsigned char b = r.blue(); In a near future the library could add the following if the users consider it useful. * Add bitfields group * Used to easily manipulate groups of bitfields the same way as does C bitfields, but in a portable manner. Example declaration: struct Rgb565 { struct red {}; struct green {}; struct blue {}; typedef bitfields<mpl::vector< member<unsigned char, red, 5>, member<unsigned char, green, 6>, member<unsigned char, blue, 5> > > type; }; Example usage: Rgb565::type r = make_bitfields<Rgb565::type, 1,2,3>; // Write to a bitfield. r.get<Rgb565::red>() = 23; //or r.set<Rgb565::red>(23); // Read from a bitfield Rgb565::at<Rgb565::blue>::value_type b = r.get<Rgb565::blue>(); * Add pointer_plus_bits * Based on a.. The article of Joaquin Optimizing red-black tree color bits, b.. the implementation of Ion pointer_plus_bits from Boost.Intrusive , and c.. Clang's QualType smart pointer This class will allows to use the unsused bits of a pointer to reduce the size of the nodes containing pointers and bits and sometimes improving also the performances. I have not reached yet the interface I would like to have. For the moment we can do typedef pointer_plus_bits<int*,1,bool>::type pint_and_bool; int i=0; pint_and_bool v1; ASSERT_EQUALS(v1.pointer(),0); ASSERT_EQUALS(v1.small_int(),false); pint_and_bool v2(&i, true); ASSERT_EQUALS(v2.pointer(),&i); ASSERT_EQUALS(v2.small_int(),true); v1.pointer()=v2.pointer(); v1.small_int()=true; ASSERT_EQUALS(v1.pointer(),&i); ASSERT_EQUALS(v1.small_int(),true); typedef pointer_plus_bits< pointer_plus_bits<int*,1,bool>::type ,1, bool>::type pint_and_bool_bool pint_and_bool_bool v1; ASSERT_EQUALS(v1.small_int(),false); ASSERT_EQUALS(v1.pointer().get_pointer(),0); ASSERT_EQUALS(v1.get_pointer().get_pointer(),0); ASSERT_EQUALS(v1.get_pointer().small_int(),false);

1 0

[interthreads] Pre-review request
by vicente.botet 19 Oct '09

19 Oct '09

Hi, I have requested the Review Wizards to include Boost.Interthreads library on the review schedule. Even if there were not too much interest for this library on this ML, there were more than 1000 dowloads from the Boost Vault. I'm open to reduce the scope of the library, if there are some parts that are not enough generic. I would appreciate it if people could participate to this Pre-review, reading the documentation, testing on their compiler, .... Every comment will help me a lot to improve the library. BTW, I'm looking for a review manager. Thanks in advance, Vicente InterThreads __________ :Author: Vicente J. Botet Escribá :Review Manager: ??? :Download: `Boost Vault: <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=intert…> Boost Sandbox: https://svn.boost.org/svn/boost/sandbox/interthreads Documentation: https://svn.boost.org/svn/boost/sandbox/interthreads/libs/interthreads/doc/… Html doc also included the Vault package :Description: Boost.InterThreads extends Boost.Threads adding thread setup/cleanup decorator, thread specific shared pointer, thread keep alive mechanism and thread tuples. * thread decorator: thread_decorator allows to define setup/cleanup functions which will be called only once by thread: setup before the thread function and cleanup at thread exit. * thread specific shared pointer: this is an extension of the thread_specific_ptr providing access to this thread specific context from other threads. As it is shared the stored pointer is a shared_ptr instead of a raw one. * thread keep alive mechanism: this mechanism allows to detect threads that do not prove that they are alive by calling to the keep_alive_point regularly. When a thread is declared dead a user provided function is called, which by default will abort the program. * thread tuple: defines a thread groupe where the number of threads is know statically and the threads are created at construction time. * set_once: a synchonizer that allows to set a variable only once, notifying to the variable value to whatever is waiting for that. * thread_tuple_once: an extension of the boost::thread_tuple which allows to join the thread finishing the first, using for that the set_once synchronizer. * thread_group_once: an extension of the boost::thread_group which allows to join the thread finishing the first, using for that the set_once synchronizer. (thread_decorator and thread_specific_shared_ptr) are based on the original implementation of threadalert written by Roland Schwarz.

1 0

[spirit] Support for one-pass iterators?
by Andrey Semashev 19 Oct '09

19 Oct '09

Hi, I'm trying to use Boost.Spirit.Classic to parse a text file content (or, to be more generic, a content that is read from an STL stream). I created a grammar that would fit the content, but I'm not sure which iterator I should pass to the parse function. The parser does not guarantee that it will read the content only in one pass, and I'm sure my actors will want to read the content themselves as they are called. So, obviously, istream_iterator/istreambuf_iterator will not work. Is there a tool in Boost.Spirit that would provide content buffering during the parse? If not, what can be suggested to solve this problem? BTW, the content is line-aligned, i.e. each line is syntactically distinct from others. I was thinking about writing a loop of readline/parse combo but I'm not sure how efficient it would be with regard to the grammar definition construction/destruction within the parse function. Are these concerns valid? Thanks.

7 31

Re: [boost] C# LINQ-like library: Boost.Qlang.
by Germán Diago 18 Oct '09

18 Oct '09

> Hi, > I read you mail on boost concerning QLang. I just wanted to say I was > wondering (not very seriously) how to do such system, and you come with a > very clean first try. > Basically it's done with some metaprogramming to get the exact return type of a query. For example, if I put as an argument in a select a pointer to member data, I extract that pointer to member's type and put it in a tuple, without const, volatile and removing the reference. I also use filter_iterator and transform_iterator from boost to filter sequences based on the where lambda. Just a suggestion : it would be great if the user of the qlang could select > a tuple of value as a return value. (let's say I want to select the string > member "_name", a copy of the pointeur "this", and an int "_age" for example > from a set of objects. I suppose returning a tuple for example (or some > other type than those of the members) could be very interesting. > I don't know very well what you mean by returning a tuple of value as a return value. For now, what the libraries does is, if you write: from(somerange).select(full_object); it will return a select_ object which will generate a copy of the full object. if you write: from(somerange).select(&MyStruct::a_, &MyStruct::b_); it will return a select_ object which will return a std::tuple<type of a_ without const and without reference, type of b_ without const and without reference>. Boost.Qlang allows you to return tuples right now, the problem is that those tuples (for now) are just 1-element tuples. But in the future they will be arbitrary tuples. A copy of the this pointer does not make sense I think. Since every piece of data is immutable (data is always generated based on the select arguments), if you want the this pointer, you will have to return full_object (a copy). So you cannot get the this pointer directly. You can manipulate that query and write it back where it belongs if you want to modify some object.

1 2

[filesystem] truncate() function?
by Beman Dawes 18 Oct '09

18 Oct '09

There was a request on the users list for a file truncate() function similar to the POSIX function of the same name. Since Windows provides a function with virtually identical semantics, this seems like a reasonable request. The POSIX spec includes: "If the request would cause the file size to exceed the soft file size limit for the process, the request shall fail and the implementation shall generate the SIGXFSZ signal for the process." I have no knowledge of or experience with POSIX signals, so need advice. Does the POSIX implementation need to do anything to cope with the possibility of a SIGXFSZ signal? If so what? Thanks, --Beman

7 12

[build] How to ignore Jamfiles?
by Sergey Zubkovsky 17 Oct '09

17 Oct '09

Hi, I there a way to ignore Jamfiles that are located in some subdirectories at a whole project's directory layout? Regargs, Sergey Zubkovsky

2 2

[Proto][MPL]Missing ADL barrier in MPL
by Joel Falcou 17 Oct '09

17 Oct '09

I've just hit a spurrious ADL resolution using MPL and Proto. I made a new function called size that took a proto expression and I get the compiler to complain about ambiguity between mpl::size<T> and my own size() function. I tried to add ADL Barrier to size by looking at how it was used in other MPL components but it still fail to resolve the proper symbol under gcc 4.3. Any idea on what to do to fix that ?

4 6

[1.41] Release Notes
by Daniel James 17 Oct '09

17 Oct '09

Hello everyone, Since we've more or less entered feature freeze, it's time to add any updates to the release notes. As always, you can just email me a line or two and I'll add it, ideally including the Trac tickets that have been fixed. Or if you want to do it yourself, the release notes directory is: https://svn.boost.org/svn/boost/website/public_html/beta/feed/history/ It would be best if you could do this before Sunday so that your changes will be included in the beta notes. thanks, Daniel

2 1

Re: [boost] [1.40.0] Compilation errors in Visual Studio
by jeremyShiers 17 Oct '09

17 Oct '09

I had the same problem the options you have listed include /Za which means disable language extensions (c/c++ ; Language ; Disable Lanauge Extensions = yes in visual studio) I changed this and it compiled who knows why changing from boost_1_39 to 1_40 should expose this. cheers Jeremy Yes, I join to this question. My setup: - VS2005 and try to compile QuantLib. - boost_1_40 Yes, I join to this question. My setup: - VS2005 and try to compile QuantLib. - boost_1_40 -- View this message in context: http://www.nabble.com/-1.40.0--Compilation-errors-in-Visual-Studio-tp253364… Sent from the Boost - Dev mailing list archive at Nabble.com.

1 0

C# LINQ-like library: Boost.Qlang.
by Germán Diago 16 Oct '09

16 Oct '09

IMPORTANT: Sorry I forgot to attach the code. This is the correct mail, ignore the other one. Hello. I'm working on a library that is very early in its development, but I wanted to share it to get some feedback and to know if someone would be interested in it. I have named the library Boost.Qlang, and, over the time, maybe I could launch it. Now about the library. Boost.Qlang is a library inspired in C#'s linq extensions. For now, as this is an early prototype, Boost.Qlang is implemented ONLY for c++0x making use of lambdas and variadic templates. The plan is to make it compatible with c++98 , but as I'm not very familiar with Boost.Preprocessor library, I sticked to c++0x to test the ideas. Now for the library, by example. The library uses this struct (for testing) and this vector: struct Person { std::string name_; std::string surname_; int age_; public: Person(const std::string & name, const std::string & surname, int age) : name_(name), surname_(surname), age_(age) {} }; vector<Person> persons = { {"German", "Gallardone", 23}, {"Pedro", "Ruiz", 28}, {"Hilario", "Pinose", 34}, {"Manolito", "Gafotas", 29}, {"Tomas", "Todonte", 56}, {"Tomas", "Ruiz", 33}}; Example 1: auto query = from(persons).where([](const Person & d) { return d.surname_ == "Ruiz"; }). select(full_object); What does this do? It selects Persons with surname "Ruiz". The full_object in select is a placeholder that selects the full object. The query is NOT executed, instead, a select_<...> object is returned, which represents a query. A query models the Range concept, so if you want to evaluate the query, you can do it like this: for (auto it = query.begin(); it != query.end(); ++it) cout << person.surname_ << std::endl; Any struct can be used for queries without any kind of adaptation. The original range cannot be modified through the query. Everything returned is a new object. If you want to evaluate immediatly the query and store it, to_list() and to_vector() can be used from the query object: vector<Person> vec = query.to_vector(); Example 2. Selecting a subset of the fields in Person. Sometimes we want to select just a subset of the fields in a query. This is done like this: auto query2 = from(persons).where([](const Person & d) { return d.surname_ == "Ruiz"; }). select(&Person::surname_); The query returns elements of type boost::tuple<std::string> containing the surname. Maybe in the future a specialized tuple will be returned, in order to access the elements in a readable way, maybe something like: get<&Doctor::surname>(elem); For now just a field can be selected at the same time in select, but the plan is to be able to select as many as necessary. There are also plans to be able to use as placeholders in select unary member functions (for now it's just pointer to member data) and lambdas. For example something like this could be done: auto myquery = from(persons).where([](const Person & d) { return d.surname == "Ruiz";}). select([](const Person & p) { return std::string(p.name_ + " " + p.surname_; }); The return type would be that of the lambda. Example 3. Nested queries: auto query3 = from(query).where([](const Person & a) { return a.age_ == 28; }). select(&Person::name_); This query holds an object with a subquery inside it. You can traverse the query and will get the expected results. For now the library, in theory, can use any class that models the range concept in the from clause. The plan would be to add xml access (I don't know much about xml, though) and for databases and so on, to get a uniform interface for data access for every single data source you can imagine. The library has been tested with gcc svn, which includes lambdas. There is a file attached to this mail with a qlangtest.cpp file in the qlang folder. The boost folder contains all the implementation. Feedback is very welcome.

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Is there a web site?
by gmane 16 Oct '09

16 Oct '09

That can answer the question of "What's new or changed in 1.41?" before the 1.41 beta comes out? Thanks

1 0

[1.41] Build files locations, try 3
by Vladimir Prus 15 Oct '09

15 Oct '09

Some time ago, I have raised the concern that CMakeList.txt files violate directory structure requirements. See: http://thread.gmane.org/gmane.comp.lib.boost.devel/189496/ I have pinged this a few times, see: http://permalink.gmane.org/gmane.comp.lib.boost.devel/193415 to no response. Now, with 1.41 going out soon, can we finally solve this issue? To rehash, the options we have are: 1. Move Jamfiles to the top-level directory of each lib 2. Move CMakeList.txt files to the build subdir 3. Adjust library guidelines. 4. Remove library guidelines, since they seem to be ignored. I hope we don't end up with option 4, of course. Thanks, Volodya

3 8

How to get the size of an C-array?
by vicente.botet 15 Oct '09

15 Oct '09

Hi, On TBoost.STM, I need to do something before deleting an array on each one of the elements of the array, or more precissely with the address of each one of the elements. T* ptr = new T[3]; // in another file, the number of elements to which ptr points is unknown. // before deleting for (size_t i=0; i< 'ptr size'; ++i) { // do something with &ptr[i] } delete [] ptr; As the number of elemenst is unknow in the separated unit, I have no mean to iterate on ptr to get the address of the elements. The C++ compiler or the C++ standard library knows this number of elements as it needs to call the destructor of each element when deleting the pointer. Is there something in Boost or a portable way to recover the number of elements of the array, maybe overloading the new [] operator and prefixing the allocate storage with some information? But what information can be stored so the implementation is portable? Any hint is welcome. Best, _____________________ Vicente Juan Botet Escribá

6 16

Re: [boost] [1.41] boost-cmake leaving svn
by pete＠pcbartlett.com 15 Oct '09

15 Oct '09

On Thu 15/10/09 07:00 , "troy d. straszheim" wrote: Eric Niebler wrote: > > Not only is it disruptive, but it's against policy to commit directly > to release. I know that, I was just trying to spin it. > My opinion: the cmake build system should be like other parts of > boost: polished, documented, tested, reviewed, accepted, merged to > trunk and then to release, and actively maintained. Please forgive me for saying this is a bit far-fetched. If I propose a library for inclusion and it gets rejected, fine, I still have a library. If I propose a build system (arguably more work than a typical library) and it gets rejected, I've got nothing. A new library doesn't typically require everybody to change the way they do business throughout the entire release cycle, from development to testing, and therefore doesn't encounter the inertia of the community. For that matter, I'm having trouble imagining how one would merge a build system from trunk to release. This is the same problem that provoked this discussion. > Distributing an experimental build system in an official boost > release was probably a mistake. Well we thought we would get some users, and we got lots of them on the end-users' side, but it didn't catch on with boost developers as I'd hoped. C'est la vie. I think the better way is: * A few notes in Getting Started with pointers to the cmake stuff * One root CMakeLists.txt that just prints a message on where to get boost-cmake * A link to some boost-cmake tarball area alongside the standard boost tarballs. That's the new proposal. > In that light, I must reluctantly agree that removing cmake from > trunk and release is probably the right thing. Beman? I doubt that it is necessary to agree at this point. That stuff either comes out of release or goes out broken. > My worry is that as a side project, the cmake build system will get > less use and less attention. It's been 2 years since the cmake effort > began, and where are we? I don't see it that way. We have 115 people on the boost-cmake list, and a bunch of them were really helpful (thanks guys) in tuning up the build for 1.40.0, and we'll do it again in a few weeks for 1.41.0. Participation has been signficantly wider than when it was just Doug and I. There are docs, happy users, all that stuff. > I *really* want our users to have a standard option for building > boost that integrates well with their chosen build environment. They've got that. It's done. -t _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost Links: ------ [1] http://lists.boost.org/mailman/listinfo.cgi/boost

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[graph] Include conflict when using spirit classic and graph libraries together
by Oliver Koenig 15 Oct '09

15 Oct '09

Hello, boost/graph/depth_first_search.hpp includes boost/spirit/home/phoenix.hpp. This include points to Phoenix2, what finally leads to conflicts if the spirit classic library (using Phoenix1) is used together with the Boost graph library. Is the spirit include in boost/graph/depth_first_search.hpp needed at all? I cannot see where something from phoenix is used in that header and in our code everything seems to work fine if I simply remove this include. Sincerely ok -- ---------------------------------------------------- Oliver Koenig EVEN - Evolutionary Engineering AG WWW : www.even-ag.ch ---------------------------------------------------- -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

2 1

[bind] bound object type introspection
by Gennadiy Rozental 14 Oct '09

14 Oct '09

Hi, Following the discussion on users list I came to conclusion it's impossible at the moment to deduce argument types of bound object passed to the function template. Is there any reason why this can't be added in the manner similar to the boost::function typedefs? Gennadiy

3 2

math/tools/rational.hpp gcc 3.2 problem
by Ralf W. Grosse-Kunstleve 14 Oct '09

14 Oct '09

gcc 3.2 doesn't compile this code (works with gcc 3.3 and up): #include <boost/math/distributions.hpp> int main() { boost::math::students_t_distribution<double> dist(1.); dist.find_degrees_of_freedom(1.,2.,3.,4.,5.); return 0; } Reduced: template <unsigned N, class T, class V> inline V evaluate_polynomial(const T(&a)[N], const V& val) { return val * a[0] * static_cast<T>(N); } int main() { double a[3]; double val; double result = evaluate_polynomial(a, val); return static_cast<int>(result); } dbg2.cpp: In function `int main()': dbg2.cpp:12: no matching function for call to ` evaluate_polynomial(double[3], double&)' Does anyone have an idea for working around the problem? Ralf

4 5

Formal Review Request: Generic Geometry Library (GGL).
by Barend Gehrels 14 Oct '09

14 Oct '09

Hi, We would like to ask for a formal review for the Generic Geometry Library (GGL). The GGL defines concepts for geometries and implements some algorithms on such geometries. GGL contains a dimension-agnostic, coordinate-system-agnostic and scalable kernel, based on concepts, meta-functions and tag-dispatching. On top of that kernel, algorithms are built: area, length, perimeter, centroid, convex hull, intersection (clipping), within (point in polygon), distance, envelope (bounding box), simplify, transform, convert, and more. The library is also designed to support high precision arithmetic numbers, such as GMP. GGL contains instantiable geometry classes, but library users can also use their own. Using registration macros or traits classes their geometries can be adapted to fulfil the GGL-concepts. The GGL might be used in all domains where geometry plays a role: mapping and GIS, gaming, computer graphics and widgets, robotics, astronomy... The core is designed to be as generic as possible and support those domains. However, for now the development has been mostly GIS-oriented. We propose the extension model, the same way as GIL also applies it. So we are going to help to organize development of GGL extensions, where an extension is (mostly) something more specific to domains like mentioned above. The proposed GGL has seen four previews, many discussions and many changes in design and implementation, based on those discussions. The last preview was in February '09. Since then the design of the library is stable and the library contains a variety of coherent functionality. So we feel that the library is matured enough for formal review. Therefore, I would like to request a formal review and the library placed into the review queue. It is put into the Boost.Sandbox: https://svn.boost.org/svn/boost/sandbox/ggl/formal_review_request We have a review manager. Regards, Barend Gehrels, Bruno Lalande, Mateusz Loskot

7 15

[test] compile-fail tests with precise output
by Jean-Louis Leroy 14 Oct '09

14 Oct '09

I would like to create tests that check, not only that a file will not compile, but that the errors contain specific strings. More precisely, I want to make sure that wrong code fails on a MPL assertion and not deep inside the template instantiations. Is that feasible? Thanks, Jean-Louis

3 2

[1.41.0] Beta planned for next week
by Beman Dawes 13 Oct '09

13 Oct '09

Looks like we are on schedule for a 1.41.0 beta next week. Now would be a good time for developers to: * Merge any stable changes from trunk to release. You can tell if there are unmerged trunk changes with the svn diff command, or use trunk/tools/release/unmerged.bat. * Check http://beta.boost.org/development/tests/release/developer/summary.html to make sure your library's tests are clean. Thanks, --Beman

2 3

Name of namespace detail
by Mateusz Loskot 13 Oct '09

13 Oct '09

Hi, Inspired by Jean-Louis question about what to put to namespace detail, I would be interested learning about rationale of name of the namespace detail (sometimes details or impl too). Recently, I've participated in a very interesting discussion, on ACCU members mailing list, about prefixes and suffixes like Base or _base nad Impl or _impl, as misused, irrelevant and confusing, meaningless, etc. For example, how to properly name elements of PIMPL idiom and similar. During the discussion I suggested that 'detail' is a good name for namespace dedicated to implementation details being not a part of public interface of a component. I got answer that it as the same issues (it's meaningless) as Impl etc. It raised some questions for myself, being interested in improving my craft, I would like to learn better about the name of namespace detail. I use detail name myself. Any better names for bucket with implementation details? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org

10 20

[signals2] combiner + groups -> topmost only (missing code)
by Oliver Kowalke 13 Oct '09

13 Oct '09

Hello, I need a combiner which executes only the slots within the highest group. How to access to group in the combiner? What happens with the input iterators if signal::disconnect_all_slots() gest called within the combiner? someting like this: struct combiner { template< typename It > void operator( It i, It e) const { // iterate over slots // execute only slots of highest group } }; signal< void(), combiner, int, greater< int > > sig; sig.connect( 0, slot1); sig.connect( 1, slot2); sig(); // only slot2 gets called regards, Oliver -- Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3.5 - sicherer, schneller und einfacher! http://portal.gmx.net/de/go/atbrowser

2 1

Deciding what to put in `namespace detail`
by Jean-Louis Leroy 13 Oct '09

13 Oct '09

For my future Boost.RDB submission, I feel tempted to put everything except the names that are in the public (documented) interface in a nested `namespace detail`. Why not even put *everything* there and copy selected names in the public namespace by means of using-declarations. Has it been already done ? And what about having three namespaces : a "public" one for the user, a "protected" one for those extending the lib, and a "private" one for undocumented internals? Opinions and advise welcome... J-L

3 2

Workaround request: boost::shared_ptr & Intel C++ Compiler
by Marat Abrarov 13 Oct '09

13 Oct '09

Hi! I wrote about my problem before (Boost-users Digest, Vol 2116, Issue 1: "boost::options, boost::shared_ptr with Intel C++ Compiler 11.x") but didn't received any response yet. So here's a copy: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I use boost 1.40. I have a project at http://sourceforge.net/projects/asio-samples/ (only SVN trunk is available now) It uses MS C++ Compiler (9.0 SP1 - MS Visual Studio 2008 SP1) and boost::program_options (+ boost::asio + boost::...). When I switched that project (I mean "echo_server") to Intel C++ Compiler 11.1.038 (I tried all 11.1.x) and built debug version (Debug Win32) (with addition of option /vmg to compiler command line - stupid Intel :) it works fine except shared_ptr-to-bool cast (for example: include/ma/echo/server/session_manager.hpp: 319). This issue I found only at "Debug Win32" build mode - at "Debug x64" all is fine and the built executable (echo_server.exe) works right. When I build "Release Win32" or "Release x64", the built executable don't work at all - it fails somewhere at the boost::program_options (I think at std::vector<std::string>::operator= or std::vector<std::string> copy-constructor). Does anybody: 1) tried to use boost::shared_ptr 2) tried to use boost::prorgam_options with Intel C++ Compiler 11.1.x? P.S. If I change boost_1_40_0\boost\smart_ptr\detail\operator_bool.hpp: 9 - add "|| defined (BOOST_INTEL)" - then shared_ptr-to-bool cast works fine (Win32/x64 Debug/Release) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Does anybody has similar problems with Intel C++ Compiler and boost::shared_ptr? Is anybody from boost community interested for Intel C++ Compiler support? Regards, Marat Abrarov.

1 0

[signals2] combiner + groups -> topmost only
by Oliver Kowalke 12 Oct '09

12 Oct '09

Hello, I need a combiner which executes only the slots within the highest group. How to access to group in the combiner? What happens with the input iterators if signal::disconnect_all_slots() gest called within the combiner? someting like this: struct combiner { }; -- Neu: GMX DSL bis 50.000 kBit/s und 200,- Euro Startguthaben! http://portal.gmx.net/de/go/dsl02

1 0

[rdb] 0.1.00 - prepared statements
by Jean-Louis Leroy 11 Oct '09

11 Oct '09

I have uploaded version 0.1.0 to the vault. It introduces prepared statements and placeholders. No doc on this yet but it's easy to use, e.g. BOOST_AUTO(st, db.prepare(insert_into(p)(p.id, p.first_name, p.name, p.age).values(_, _, _, _))); st.execute(3, "Bart", "Simpson", 9); st.execute(4, "Lisa", "Simpson", 7); st.execute(5, "Maggie", "Simpson", 0); It also works with update, delete and select. Placeholders are allowed in predicates as well. Parameters are type-safe, if they don't agree with the type of their corresponding placeholder (as deduced by the context in which it is used), you will get a compilation error. More examples in the test file here : http://code.google.com/p/boost-rdb/source/browse/libs/rdb/test/test_odbc.cpp J-L

1 0

[wave] 1.40.0 build problem on recent intel
by troy d. straszheim 10 Oct '09

10 Oct '09

Over on the boost-cmake Justin Holewinski pointed out that wave doesn't build on recent intel compilers. Details and fix here: http://software.intel.com/en-us/articles/error-409-when-building-boost-libr… -t

2 1

Re: [boost] threads: how to remotely kill a thread?
by David M. Cotter 10 Oct '09

10 Oct '09

yes i have seen the error of my ways, and am now using thread.interrupt () and i sprinkle interruption_point() in my inner loops of the thread thanks for the feedback. -dave On Oct 9, 2009, at 9:20 PM, Yigong Liu wrote: > It is kind of dangerous for one thread to kill another thread > forcefully or directly, since the 2nd thread may be in the middle of > holding a system resource or changing some state. Killing it may > left the system in corrupted state. better using "cooperative" > shutdown, the 1st thread sends the 2nd thread some notification, > either thru shared state or interrupt. For similar reasons, java > deprecated many thread api (http://java.sun.com/j2se/1.4.2/docs/guide/misc/threadPrimitiveDeprecation.h… > ). > > On Fri, Oct 2, 2009 at 9:16 AM, Andrey Semashev <andrey.semashev(a)gmail.com > > wrote: > David M. Cotter wrote: > say i'm on the main thread, and i've got a thread::id of some other > preemptive thread. i do not have the actual boost::thread object > any more. > > and i want to unceremoniously kill that thread. like right now. > > how do i kill it? i don't see a way to recover the actual > boost::thread from the thread::id. but even if i could, and then > call thread.interrupt(), that's more of a polite request which is > free to be ignored, rather than a you_must_die_now() thing. > > The main problem with killing threads is that it doesn't unwind the > stack and thus breaks RAII. Therefore the best "official" way to > terminate the thread in C++ is to interrupt it. If you want to do it > the hard way, you're in C world with pthread_kill and alikes.

1 0

[fusion] accumulate vs. std::accumulate
by Christoph Heindl 10 Oct '09

10 Oct '09

Hi, I'm currently confronted with an issue raised before [1] on this list: boost::fusion::accumulate takes its arguments in reverse order compared to std::accumulate. The issue is still marked as 'new' on trac [2]. What are the chances to have this issue fixed for the next release? Kind regards, Christoph [1] http://lists.boost.org/Archives/boost/2008/09/142490.php [2] https://svn.boost.org/trac/boost/ticket/2355

1 0

[trunk] Missing Jamfile in Boost Root Directory
by Dean Michael Berris 10 Oct '09

10 Oct '09

Hi everyone, I just did an SVN update to the latest in Boost's trunk and I don't see a Jamfile in the root directory anymore. I ask because I do this in my project Jamroot, which used to work: import os ; local BOOST_ROOT = [ os.environ BOOST_ROOT ] ; use-project /boost : $(BOOST_ROOT) ; But now when running bjam it complains that it can't see a Jamfile in the BOOST_ROOT directory. Any workarounds for this? TIA -- Dean Michael Berris blog.cplusplus-soup.com | twitter.com/mikhailberis linkedin.com/in/mikhailberis | facebook.com/dean.berris | deanberris.com

2 1

[MPI?] which API should i use for this?
by David M. Cotter 10 Oct '09

10 Oct '09

I have a need to send an "event" to the "main thread's event loop". this may be done from a preemptive thread, a cooperative thread, a timer, or even the main thread itself. i want it to be posted into the event stream and handled in the order that events get processed on the main thread. would i use 'MPI'? or 'interprocess'? or is there a 'thread' way to do this? if it's MPI, what would be the right call? i'm coming from Mac land where i have traditionally used PostEventToQueue()

5 5

[Boost.Units] non-integral unit exponents
by Belcourt, Kenneth 09 Oct '09

09 Oct '09

Hi, I'd like to use Boost.Units but am unsure whether I can declare a unit like this: W/m^2 Pa^0.25 K^1.523 In addition, I'd like the ability to change the pressure (Pa) and temperature (K) coefficients at runtime (user supplied input might change the default coefficients). Are these things possible with Boost.Units and, if so, could someone point me to an example? (I need this for nucleate boiling curves). Thanks. -- Noel

2 1

threads: linking on OSX
by David M. Cotter 09 Oct '09

09 Oct '09

I followed the instructions from here: http://www.boost.org/doc/libs/1_40_0/more/getting_started/unix-variants.htm… and it spent a bunch of time compiling everything. no errors. yay. so then i go to link my program, i added <boost dir>/stage/lib/ libboost_thread.a to my project, cuz that's how you static link, right? where <boost dir> is the location of the boost installation but it says: <boost dir>/bin.v2/libs/thread/build/darwin-4.2.1/release/threading- multi/libboost_thread.dylib, file is not of required architecture Undefined symbols: <long list of all the boost symbols i used> interesting that even by adding the .a file, it went and found the dylib? is that normal? anyway, wrong architecture?? how do i make it build universal? (PPC plus intel? and what's with the missing symbols? i'm not really a n00b, i just appear to be one today.

3 4

[parameter] Ticket #3114
by Jeremiah Willcock 09 Oct '09

09 Oct '09

Would it be possible to have the feature requested by ticket #3114 (https://svn.boost.org/trac/boost/ticket/3114) implemented? This would make the Boost.Parameter library much more useful for situations where default argument types do not always exist. Thank you. -- Jeremiah Willcock

1 0

[Property map] 1.40.0 breaks boost.graph python bindings
by John Reid 09 Oct '09

09 Oct '09

I'm using gcc 4.2.4 on Ubuntu. The boost.graph python bindings (http://www.osl.iu.edu/~dgregor/bgl-python/) work fine with boost 1.39. When I try with boost 1.40 I get many errors such as the following: ./boost/graph/python/resizable_property_map.hpp:101: error: ‘class boost::vector_property_map< boost::default_color_type, boost::graph::python::basic_index_map< boost::graph::python::basic_descriptor<boost::detail::edge_desc_impl<boost::bidirectional_tag, void *>, boost::bidirectionalS>, boost::adj_list_edge_property_map< boost::bidirectional_tag, long unsigned int, const long unsigned int &, void *, const boost::property<boost::edge_index_t, long unsigned int, boost::no_property>, boost ::edge_index_t>>>’ has no member named ‘get_store’ Does anyone know what changed between 1.39 and 1.40 to break this? The Readme.txt that comes with boost 1.40 suggests that nothing was updated in the property map library. BTW it doesn't compile with gcc 4.3 either but then neither does it compile with boost 1.39 (albeit for different reasons). I can provide all of the error messages if needed. John.

1 0

[1.41.0] Cleaning up inspection errors
by Beman Dawes 09 Oct '09

09 Oct '09

The Inspection Report is showing 1292 problems reported. I'd like to drive that number way lower for the 1.41.0 release. The "Worst Offenders" list is: test (254) regression (145) gil (140) build (116) proto (75) See http://boost.cowic.de/rc/inspect-trunk.html Developers, please fix any problems in your library. Thanks, --Beman

2 2

[program-options] Ticket #1132, multitoken() and zero_token()
by Sascha Ochsenknecht 09 Oct '09

09 Oct '09

Hello, I would like to have an option which allows multi token but not multiple occurrences of the option or at least a way to distinguish the occurrences: E.g. something like: program.exe --option value1 value2 I tried the following: 1) desc.add_options()("option", value<string>()->multitoken(), "help"); With the above command line I get exception: multiple values not allowed 2) desc.add_options()("option", value<vector<string> >(), "help"); Command line is parsed without error but only value1 is stored in the vector -> ERROR, should report 3) desc.add_options()("option", value<vector<string> >()->multitoken(), "help"); Command line is parsed without error both values are stored in the vector, but program.exe --option value1 --option value2 and program.exe --option value1 value2 leads to the same vector contents. With the current version it isn't possible to distinguish to occurrences of a certain option and it is not possible to implement an option which has the multitoken attribute but isn't allowed to occur several times. I'm willing to work on a patch for this issue, but first I want to discuss how to solve this, i.e. how the library should behave. The problem is possibly that specifying a list or vector implies that an option can occur multiple times. I think maybe following solution could work: 1) desc.add_options()("option", value<vector<string> >(), "help"); multiple occurrences of the option are allowed and pushed to the vector but only one value per option occurrence (like it is implemented now) 2) desc.add_options()("option", value<vector<string> >()->multitoken(), "help"); multiple occurrences of the option are NOT allowed, the multiple tokens/values are pushed to the vector 3) desc.add_options()("option", value<vector<vector<string> > >()->multitoken(), "help"); multiple occurrences of the option are allowed, the multiple tokens/values are pushed to the inner vector E.g. program.exe --option value1 value2 --option value3 --option value4 value5 This would result in the following storage sheme: { { value1, value2 } { value3 } { value4 value5 } } I'm not sure if a could become a friend of this implementation ... but it would work at least. Another way would be to join the multitokens into a single string: { "value1 value2" "value3" "value4 value5" } .. but this I don't like :-(. What do you think? Thanks & regards, Sascha PS: Is somebody working on ticket #1132 ??

1 0

[rdb] 0.11
by Jean-Louis Leroy 08 Oct '09

08 Oct '09

In this drop : * Everything related to SQL composition has been moved to namespace boost::rdb::odbc * Update syntax has changed, instead of .set().set() chains it is now closer to SQL syntax (an deasier to implement): update(p).set(p.id = 1, p.first_name = "Homer") * Qualified table names: person::qualified p; partner::qualified l; select(p.id).from(p, l).where(p.id == l.wife) gives: select person.id from person, partner where person.id = partner.wife * in predicate: select(p.id).from(p, l).where(p.id.in(select(l.husband).from(l))) select(p.id).from(p).where(p.id.in(p.age + 1, 2)) * NULL: insert_into(p)(p.id, p.age).values(1, null) update(p).set(p.age = null).where(p.id == 1) select(p.id).from(p).where(p.age == null) Whoa! This gives: select id from person where age is null I'm only 80% sure about this one. Like everybody I suppose I have tried one day to compare with NULL, only to realize that the result is always false. After a while, ahem...So I have implemented operator == to do the right thing. It could have been: select(p.id).from(p).where(p.age.is_null()) Does anyone has an example where it makes sense to truly compare (using =) with NULL ? As for returning the NULL indicator when reading results, I chose not to use Boost.Optional (although I will probably add support for optional as well) because: 1. it would cost one bool (most likely the size of an integer) per column 2. IMHO the automatic conversion to bool is a bad idea 3. the value inside an optional<> cannot be addressed Instead I have complemented a fusion::vector with a std::bitset. The tutorial shows how to use this. I am hesitating a bit about pushing fusion::vector inside the implementation (i.e. nullable<int, char...> instead of nullable< fusion::vector<int, char> >). * Result sets: execute(Select) now returns a ResultSet object that allows retrieval row by row: also see the tutorial here : http://yorel.be/boost/libs/rdb/doc/html/rdb/tutorial.html#retrieve_data There is also a "Jumbo select" at the bottom of the tutorial that recaps everything that is supported for the moment. J-L

5 10

[threads] wait() and signal() ?
by David M. Cotter 07 Oct '09

07 Oct '09

on the mac the notion of a semaphore is at a slightly higher level than a condition_variable. but it seems in boost::thread we must use the actual condition_variable. on the mac, with a semaphore, the value can be pre-set to signal, so that the next wait() is passed right thru, since the signal was sent ahead of time. eg: you could do this: Semaphore sem; // newly initialized semaphore, brand new, never waited upon sem.signal(); // you can pre-set the signal! // later in the code sem.wait(); // no wait, since signal was already sent // and later still sem.wait(); // now we wait in fact, actually, the way it actually happens on the mac is that a newly initialized semaphore comes IN WITH the semaphore pre-signaled. so you actually have to call wait() immediately to eat that signal. i've got lots of code that does this: Semaphore sem; sem.wait(); // eat the first signal i thought that was normal. trouble is,i've got lots of code that does NOT eat that first signal, depending on the first wait call to be passed thru immediately. this is the code that now breaks. in converting to boost::thread, there doesn't seem to be a way to pre- set the signal. or to reset the state of a semaphore from an unknown state to a known state, eg this code: sem.signal(); sem.signal(); sem.wait(); that guarantees that the next wait will actually wait, regardless of the state of the sem before hand. how can i do this with boost::thread ?

6 7

[rdb] Repository, contributing, copyright, etc
by Jean-Louis Leroy 07 Oct '09

07 Oct '09

* Respository I have set up a Mercurial repository for rdb. You can get a copy with this command: hg clone https://boost-rdb.googlecode.com/hg/ boost-rdb You can view the source without installing Mercurial at that URL. * Contributing For those who consider contributing: I would like to keep clear copyright on this work. I propose the following arrangement: if you send me a patch that touches any of my copyrighted files, and I decide to use it, then you agree to transfer the copyright on the entire patch content to me. In return, I guarantee: 1/ the files touched by the patch will remain available under the Boost license 2/ you will get credit for it in the "Acknowledgements" section of the doc. If you create a set of files that is independant from mine and wish to put it in the distributions or in the repository, then you retain the copyright on them and set the rules you want. What I have in mind here is a native binding to a database. I hope that by next year we will have native bindings for all the major databases and obviously I am not going to write them all by myself. * Please help I am looking for the sql 2003 syntax expressed as a graph, preferably available online. Books suggestions are welcome too. * Extensibility For a small touch of technical stuff in this mail: I am trying hard to make it easy to support the various dialects. Here is a proof of concept (add MySQL LIMIT clause): https://boost-rdb.googlecode.com/hg/libs/rdb/doc/examples.cpp J-L

1 0

[utility] auto_buffer v2
by Thorsten Ottosen 07 Oct '09

07 Oct '09

Dear All, Hereby an updated class. Thanks to all who contributed with comments to the first try. I have made the following changes: 1. push_back() overloads are now growing 2. added swap() (boy, was this nasty to implement). I assume the allocator can be wapped without throwing. How do other people copy with this problem? 3. added copy-constructor + copy-assignment 4. made the min capacity equal to N, the number of elements in the stack buffer 5. the size of the internal buffer is now controlled via two policies: template< unsigned N > struct store_n_objects; template< unsigned N > struct store_n_bytes; the default is store_n_objects<256>. The reason is that we don't want the capacity to change just because we compile on a different platform. 6. added comparison operators Comments most welcome! best regards -Thorsten

4 7

[asio] confused by multiple socket flavors
by Roland Schwarz 07 Oct '09

07 Oct '09

There is a stream_socket_service and a ip::tcp::socket class, with almost the same member functions. I do understand that the first "is_a" service while the second "has_a" service. Is there any rationale beyond just having both? When would I want to use which one? Do I have overlooked something in the documentaion? Any hints appreciated. Roland -- _________________________________________ _ _ | Roland Schwarz aka. speedsnail |_)(_ | sip:speedsnail@ekiga.net | \__) | mailto:roland.schwarz@chello.at ________| http://www.blackspace.at

1 0

custom async devices
by Roland Schwarz 07 Oct '09

07 Oct '09

Recently I had a question about how I could use asio for performing asynchroneous file IO. In the meantime I found that there are already some classes for doing async_read_at IO on handles, but only for windows. Since I need to address multiple platforms I am wondering how I would go about that. I am thinking of an emulation layer in user-space based on threads. I guess I could set up a thread-pool that will accept async call ins. The thread pool would know about an io_service and when a task, e.g. a file IO has completed, use the post function on the io_service to invoke the completion handler. Is this a reasonable design? Any pros/cons? Does anyone know of an example that I could use as a starter? Thank you, Roland -- _________________________________________ _ _ | Roland Schwarz aka. speedsnail |_)(_ | sip:speedsnail@ekiga.net | \__) | mailto:roland.schwarz@chello.at ________| http://www.blackspace.at

1 0

how to mark test as "expected fail" for some toolsets
by Gunter Winkler 07 Oct '09

07 Oct '09

Hello, I'd like to mark the begin_end test of uBLAS as compile-fail for MSVC 7.1 ([1]). However I was not able to figure out how this works. Does anyone have some insights (or maybe a patch) to do this? [1] http://www.boost.org/development/tests/trunk/developer/output/daw-msvc71-bo… mfg Gunter

3 3

Bjam outside Boost tree
by Jean-Louis Leroy 06 Oct '09

06 Oct '09

I am working on a lib that is laid out in typical boost fashion: a directory with boost/rdb/includes.hpp, libs/rdb/src/stuff.cpp. When I put these two directories right inside a Boost tree that builds properly with bjam, I can build my libs as well (via chdir to libs/rdb/test and run bjam). I managed to get that much working. Now I would like to build outside the boost tree. I have found this message:http://lists.boost.org/boost-build/2002/11/2221.php but the link it contains is broken. I have tried to locate the information in the doc for half an hour now, without success. I tried to set BOOST_BUILD_PATH AND BOOST_ROOT to point to the boost tree. And copied boost-build.jam to the root of my dir. Can someone help me with this please? TIA, J-L

3 14

simple range adapter
by Neal Becker 06 Oct '09

06 Oct '09

I'd be surprised if others haven't needed this. While range comes with an adapter for plain old C array, it doesn't come with an adapter from that other (probably more common!) kind of plain old C array: a pointer and length. This seems useful. Maybe add to examples?

3 6

svn.boost.org has invalid ssl certifcate
by Markus Werle 06 Oct '09

06 Oct '09

Hi! Maybe this is only an issue with paranoid or misocnfigured firefox, but annoying anyway, since I change platforms very often. firefox reports: svn.boost.org uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer) Can this be fixed on the server side? best regards, Markus

4 3

[Variant]
by Cosimo Calabrese 06 Oct '09

06 Oct '09

Hi to all, I've looked at the following example: http://www.boost.org/doc/libs/1_40_0/doc/html/variant.html#variant.motivati… and I think that miss an include: #include <string> Best regards, Cosimo Calabrese.

2 1

Off-topic question about Boost trac
by Mateusz Loskot 05 Oct '09

05 Oct '09

Hi, First, forgive me I'm sending this off-topic question to the mailing list, but I'm actually not sure where it would belong. Probably, I should direct my question to Boost Trac admins, but I don't know how to reach them. So, here we go: I'm involved in OSGeo Foundation and we maintain number of Trac instances (http://trac.osgeo.org/) for our projects. For longer while, we've been experiencing server load issues related to Trac. I noticed that Boost Trac displays "Server Load Average" information in below the menu bar. I would like to setup the same feature for OSGeo but I can not find any information how to do it. Could you tell me how you've got this for Boost Trac? Perhaps you could also tell me why you've decided to display this "Server Load Average" information in the Boost Trac? Does it mean Boost were experiencing load issues? Thanks for your help! Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org

1 0

[task] reschedule_until
by Baxter Jeremy 05 Oct '09

05 Oct '09

> Date: Fri, 2 Oct 2009 18:59:10 +0200 > From: k-oli(a)gmx.de > Subject: Re: [boost] [task] > > Second - I'm finishing boost.task-0.4.0 which replaces > this_task::reschedule_until() by this_task::block(). > block() suspends the current task without blocking the > worker-thread. The > blocked task gets rescheduled by the internal scheduler > (returning from > block()): > > while ( ! condition) > this_task::block(); > > Version 0.4.0 allows to synchronize or exchange messages > between the tasks > without deadlocking the threadpool (that means amount of > tasks >> worker- > threads in pool). > > regards, > Oliver Thanks - I'll steer clear of using reschedule_until at the moment. Being able to block a task without locking out the worker thread would be useful for me, but I suspect my requirement may be rather different to yours. I'm pretty much assuming amount of tasks == worker-threads in pool. My main interest in a thread pool is to avoid creating and destroying a new thread each time a task has to run but I suspect I may use task or threadpool it this way initially and see what the overhead is like. Jeremy The information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). The information in this communication may be confidential and/or legally privileged. Nothing in this e-mail is intended to conclude a contract on behalf of QinetiQ or make QinetiQ subject to any other legally binding commitments, unless the e-mail contains an express statement to the contrary or incorporates a formal Purchase Order. For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful. Emails and other electronic communication with QinetiQ may be monitored and recorded for business purposes including security, audit and archival purposes. Any response to this email indicates consent to this. Telephone calls to QinetiQ may be monitored or recorded for quality control, security and other business purposes. QinetiQ Limited Registered in England & Wales: Company Number:3796233 Registered office: 85 Buckingham Gate, London SW1E 6PD, United Kingdom Trading address: Cody Technology Park, Cody Building, Ively Road, Farnborough, Hampshire, GU14 0LX, United Kingdom http://www.qinetiq.com/home/notices/legal.html

2 1

[task] reschedule_until
by Baxter Jeremy 05 Oct '09

05 Oct '09

- my example and some of Vicente's comment snipped - > > I think that it will not to much complex to provide a > function that submit a task that must run on the context of a > different thread. Would this kind of submit function help you? > I'm not sure that it would help, I think that I could construct a more complex example with more tasks and threads that would still deadlock. In general I think it ought to be a requirement that the threadpool works if it has only a single thread (in which case the above would not work). > > I'm not sure that there is a general solution to this > problem without > > using more threads so that any potentially runnable task will get a > > chance. > > You are right this should be a deadlock problem with the > current implementation. > I don't think however that having more threads would solve > the issue, but just reduce its frequency, as the issue > appears when tasks T1 and T2 are handled on the same thread. > I agree, that is why I was not keen on reschedule-until. If blocking is used I think an unexpected deadlock could occur unless all blocked tasks can be resumed in any order, not strictly in reverse order of their reschedule calls as in the current implementation. > In order to avoid the issue we need to avoid two blocking > tasks to be executed on the same thread. The user should state > blocking task on the submit function. The scheduler will not > take a blocking task while in the reschedule_until function. > Of course, in order to be able to avoid any deadlock > associated to the fact we are using a thread pool, the number > of threads must grow, if there is no free worker threads able > to handle the new blocking task. The reschedule_until > function should throw an exception when the task is not a > blocking task. > > This should solve the issue, but introduce a burden at the > user level, i.e. specify if the task can block or not. > > Jeremy, Oliver, what do you think? > > Best, > Vicente > > I think Oliver's intention to use a fiber style scheduler is the right one. To avoid problems all possible mechanisms of blocking would need to be considered and protected against and the temptation would be to declare most tasks as blocking. Even if tasks don't block they may run on the thread for a long time before returning. A dynamic thread pool would also be a solution, starting more threads as tasks block and cleaning them up when the queue is empty. This is the approach used in the Java Executors class (http://java.sun.com/j2se/1.5.0/docs/api/java/util/concurrent/Executors. html). I'm not sure if there is a way to detect the difference between threads being busy and being blocked as in general you would like to keep the number of unblocked threads down to the number of cores. Jeremy Jeremy Baxter Lead Researcher, UAVs & Autonomy Tel: 01684 894801 email: jwbaxter(a)QinetiQ.com www.QinetiQ.com QinetiQ - Delivering customer focused solutions Please consider the environment before printing this email. The information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). The information in this communication may be confidential and/or legally privileged. Nothing in this e-mail is intended to conclude a contract on behalf of QinetiQ or make QinetiQ subject to any other legally binding commitments, unless the e-mail contains an express statement to the contrary or incorporates a formal Purchase Order. For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful. Emails and other electronic communication with QinetiQ may be monitored and recorded for business purposes including security, audit and archival purposes. Any response to this email indicates consent to this. Telephone calls to QinetiQ may be monitored or recorded for quality control, security and other business purposes. QinetiQ Limited Registered in England & Wales: Company Number:3796233 Registered office: 85 Buckingham Gate, London SW1E 6PD, United Kingdom Trading address: Cody Technology Park, Cody Building, Ively Road, Farnborough, Hampshire, GU14 0LX, United Kingdom http://www.qinetiq.com/home/notices/legal.html

2 1

Re: [boost] [rdb] rdb/persistent integration
by strasser＠uni-bremen.de 05 Oct '09

05 Oct '09

>> also, you could use more than one resource managers at a time, so you could >> have distributed transactions between two databases, between a file and a >> database, etc., and can have references across resources. (a locator can >> reference an object in any resource, and can be stored as part of an object) >> > Very interesting project. At this point my feeling is that there is room > to slip not one but two of my libs under yours ! > what`s the other library? btw, I wasn`t suggesting we should merge our libraries. a stand-alone sql db layer definitely makes sense. even a standalone o-r mapper might make sense, depending on what kind of user interface you planned for it. it might e.g. be better for some use cases to give the user more control over when and how actual SQL is produced and objects are stored than my library does. much like my resource manager uses Boost.Serialization, but doesn`t replace Boost.Serialization. remember that my intent was a user interface as close as possible to using regular objects in memory, so there is no "store this object now" function. the resource manager is free to cache and postpone accesses to the storage engine, as long as it guarantees that the object is stored on transaction::commit the latest. but we should work together on "linking" the libraries, i.e. implementing a boost.persistent resource manager that uses your o-r mapper, in the current design. or merge your o-r mapper library with my library, but leave the sql db layer a seperate library. depending on the o-r mapper interface you planned.

1 0

Looking for a name for a Subjet-Entity-Role library
by vicente.botet 05 Oct '09

05 Oct '09

Hi, I'm developing a library based on the Object Role pattern. The library use the following concepts: Entity, Role, Subject, Cloture. Its main goal is to help on subjetive programming. I was started to name this library SER (for Subject-Entity-Role). Next follows some Entity-Role-Subject declarations class Person : public entity<Person> {...}; template <typename Base> class PersonRoleTmpl : public basic_role<Person, Base> {...}; class PersonRole : public PersonRoleTmpl<> {...};class Employee : public role<Employee,PersonRole> {...}; class Salesman : public Employee {...}; class Developer : public Employee {...}; class Manager : public Employee {...}; class Guarantor : public role<Customer, PersonRole> {...}; class Customer : public role<Customer, PersonRoleTmpl<entity<Customer> > > {...}; class CustomerRole : public basic_role<Customer> {...}; class Borrower : public role<Borrower, CustomerRole> {...}; class Investor : public role<Investor, CustomerRole> {...}; class CustomerAndEmployee : public subject<Person, roles<Customer,Employee> > { ... }; Any sugestions for the name of the library, 'Subjetive', 'SER'? Best, _____________________ Vicente Juan Botet Escribá

5 7

[sandbox] Mysterious (?) commit messages, 'm', 'a', 'd'
by Niels Dekker - address until 2010-10-10 04 Oct '09

04 Oct '09

There appear commit messages of a single letter: 'd', 'm', 'M', 'a'. Or combined: "m/a". It seems like they only appear in the sandbox. https://svn.boost.org/trac/boost/timeline What do they mean? (Maybe "e_r" can tell us.) FWIW, I'd rather see more "human friendly" commit messages. Thanks in advance, Niels -- Niels Dekker http://www.xs4all.nl/~nd/dekkerware Scientific programmer at LKEB, Leiden University Medical Center

2 1

GIL extensions home and guide
by Mateusz Loskot 04 Oct '09

04 Oct '09

Hi, May I ask for update where is most current home for Boost/Adobe GIL library extensions [0]? What's the difference beetween extensions in Boost SVN [1] and those hosted in Google Code [2] ? Second, what document should one refer to learn about developing new I/O extensions for GIL? The GIL Design Guide [3] is quite dated, from 2007 [0] http://opensource.adobe.com/wiki/display/gil/Contribute+to+GIL [1] https://svn.boost.org/trac/boost/browser/trunk/boost/gil/extension/ [2] http://code.google.com/p/gil-contributions/ [3] http://www.boost.org/doc/libs/1_40_0/libs/gil/doc/html/gildesignguide.html Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org

2 2

[rdb] 0.0.09
by Jean-Louis Leroy 04 Oct '09

04 Oct '09

In this version : * EXISTS * consistency check in INSERT...SELECT * DISTINCT, ALL * transactions The transaction stuff is pellicular. It simply maps to vendor calls. I am hesitating a bit, either make a common interface for the most common operations (like execute) directly in each backend (aside with vendor-specifc calls) or put them in a separate wrapper or even decide that it's not in the scope. There's more redesign in the select from which I think I can get an elegant implementation of vendor-specific features (like LIMIT). The idea is to pass all the data in a fusion map, allowing vendor specific parts of the statement to slip their own data inside it. In fact this also is how DISTINCT works. I dropped the composition of lists via chained calls to operator (). It's all preprocessor-based now. The () chain system was limited by FUSION_MAX_VECTOR_SIZE anyway. I have installed MySQL on my computer. I am still accessing it via ODBC but I'll probably start the native support soon. Yesterday I tried to upload and just when I pushed the upload button the vault server crashed. I suspect that it was my upload that triggered it. J-L

6 15

[trac] Make me property_tree owner
by Sebastian Redl 04 Oct '09

04 Oct '09

Hi, Could somebody who has the authority to do so please make me (cornedbee) the owner of property_tree? Currently, all PTree tickets are still assigned to kaalus, who is the original author. Sebastian

2 1

[Fusion] port to c++0x
by Christopher Schmidt 04 Oct '09

04 Oct '09

I participated in Google's 'Summer of Code' for Boost this year. My project was to port Boost.Fusion to c++0x. The program is over now and I would like to give you a short report on my work and put my code up for comments. In a nutshell, there is rvalue support, native variadic templates are used if possible and the public classes and (meta-) functions are guarded by a set of static asserts that detect most invalid (template) arguments. I also added certain new functionality to provide an easier, faster and more intuitive programming interface. My implementation is pretty much backwards compatible and all test cases pass on gcc 3.4/4.4 and vc 9. Here is a short overview of the most striking changes besides the implementation of raw c++0x support. I removed the deque container and the extension-classes. The deque container is undocumented and, in my opinion, does not go well with the other container due to its intrinsic extension mechanism. There also should not be a performance gain compared to a regular fusion::joint_view in combination with two fusion::vector. The extension classes are pretty much Boost.Proto specific. At the moment they seem to be out of place, especially as they are undocumented, unmaintained and not even part of the regular file structure. I would like to see them either fully documented (with the underlying concept of segmented sequences) or in the detail namespace of Boost.Proto. I added support for associative iterators. An associative forward sequence shall provide an iterator type which implements the extension backend of the intrinsic (meta-)functions fusion::result_of::value_of_data, fusion::deref_data and fusion::result_of::key_of. This has the advantage that all view classes, even fusion::iterator_range, are able to adapt the underlying sequence's associative-ness. fusion::transform_view, as a special case, got an additional template parameter. This parameter specifies whether the view should model either the forward concept only or the associative and the forward concept. This design breaks consistency with Boost.MPL. Unfortunately these changes are crucial and I would rather risk this break with Boost.MPL than missing that important feature. Using the old implementation, there is no way to avoid explicitly converting from a view back to an associative sequence to preserve the associative-ness. This leads to a nasty runtime overhead due to evaluation of every element of the view and copy-/move-constructing it. Besides, other changes include: -If the compiler supports rvalue references, all fusion container have a template constructor (taking either const lvalue or 'templated' rvalue references). -If the compiler supports variadic templates, fusion::cons, fusion::pair and fusion::single_view have a variadic template constructor (taking either const lvalue or 'templated' rvalue references) that allows emplace construction. -The view classes adapt the full category of their underlying sequences. As mentioned above, the associative-ness is preserved, but also, if possible, the random-access or bidirectional trait. -The result_of::-metafunctions accept r- and lvalue references arguments. If an argument is not reference-qualified, it will be considered to be an lvalue reference. All existing extension implementations must be changed to adapt this new behaviour. -The algorithm functions now also take (and correctly forward) non-const reference arguments. -Fusion iterators (with reference compatible sequence types and a very same index) and views (with reference compatible sequence types) have a working operator= that correctly reassigns the underlying sequence references. -Fusion now also adapts MPL iterators. If, and only if, the <boost/fusion/adapted/mpl.hpp>-header is included, mpl sequences and iterators are recognized as fusion sequences and iterators. -There are new headers to adapt std::(tr1::)array or std::(tr1::)tuple. The overall compile-time performance of my code is satisfying. Compiling a compilation unit that includes all possible fusion headers takes on gcc 4.4 slightly more time than the official fusion implementation. If native variadic templates are present, the compilation is a lot faster (usually up to 3 to 6 times), regardless of the value of FUSION_MAX_xxx_SIZE. The compile-time performance of actual fusion code is mixed. The intrinsic container and iterator (meta-)functions compile a little bit slower compared to the official fusion implementation. This is due to explicit removal of the references on the arguments of all result_of::metafunctions and some additional abstraction layer. If the compiler support rvalue references, there has to be a rather ugly and slow type evaluation/transformation to avoid issues with rvalue references on non-array, non-class types (see /support/internal/ref.hpp and 8.5.3p5 of the current c++0x draft for more details). On the other hand, I added several optimizations (such as result preevaluation), and, if variadic templates are present, the actual instantiation of fusion containers is a lot faster. All in all, the compile-time performance is a little bit worse if c++0x features are not present. If c++0x features are present, the code should compile a little bit faster in most cases. For example, the lambda example of the Boost.Proto documentation, which internally heavily relies on Boost.Fusion, takes on my machine 2.6 seconds to compile with the 'old' fusion on gcc 4.4, 3 seconds with my port without -std=c++0x, and 2.1 seconds with c++0x features being present. The overall performance might be even better once Boost.MPL adapts native variadic templates and the compiler supports template aliases. There have been tons of other changes, mostly bugfixes, optimizations (in terms of compile time of course) and removals of redundancy. Whenever I had the choice, I tried to prefer clean, redundancy-free instead of heavily optimized code. The overall performance loss is not noticeable though, and most compile-time optimizations that go beyond the as-little-template-instantiations-as-possible paradigm are pretty much compiler dependent anyway. There is still some work to do. I did not add c++0x-specific test cases and there are several parts of the documentation which need to be updated. By the way, are there any official guidelines for documenting c++03/c++0x-specific differences? For now, I would like to hold off on implementing these changes until Boost.TypeTraits adapts c++0x. Right now I implemented missing or incorrectly behaving trait functions in the fusion::detail-namespace. I would rather like to use the official ones, at least in the documentation and in the test cases. Besides that, I think my implementation is trunk-ready. If there are no objections, I would like to finish the outstanding work as soon as possible, and then merge my code with the trunk. Of course I will provide long-term support for the project. In fact, I would love to become an official fusion maintainer. You can find the code in the boost sandbox (/sandbox/SOC/2009/fusion). If you test the code with a compiler that has decltype support, please use the HEAD of the trunk rather than the official 1.40 distribution package to compile your code. Best regards Christopher

6 17

Review Request: Boost.Itl; The Interval Template Library
by Joachim Faulhaber 03 Oct '09

03 Oct '09

Dear developers, the Interval Template Library is now in a state where I think it does conform the requirements and guidelines for boost libraries fairly well. To decide, whether it's design, implementation and overall usefulness is sufficient to be accepted in the boost libraries collection is now up to you. In the last round of refactoring I concentrated on efficiency and optimization issues. The implementation of the itl's interval containers is still based on std::set and std::map, but algorithms are now exploiting hinted insert and are manipulating intervals and values in place instead of copying in many instances. This way, it has been possible to improve performance significantly. Along the way of implementing optimizations I have documented the complexity guarantees for all important functions of the library's interface. Please note that the original ITL as presented in May 2008 has been split into 3 parts and only the *first* part is submitted for review: itl : Core library, interval containers, SUBMITTED FOR REVIEW Additional parts are: itl_xt : Extensions like histories and generalized crosstables validate: The law based test automaton (LaBatea). A validation tool using laws aka axioms. *itl* is a complete library containing all required ingredients particularly a separate test suite (NOT using LaBatea) and the quickbook documentation. The code is successfully compiled and tested with gcc-3.4.4, 4.1.0, 4.3.2 and msvc-8.0, 9.0. I have uploaded the review version as itl_3_1_0.zip to the vault in section containers. http://www.boostpro.com/vault/index.php?action=downloadfile&filename=itl_3_… Another file itl_plus_3_1_0.zip contains all three parts (itl, itl_xt and validate). http://www.boostpro.com/vault/index.php?action=downloadfile&filename=itl_pl… Reviewers interested in the law based testing part may have to refer to this file to examine those tests. The law base testing examples compile and run with gcc-4.3.2, msvc-8.0 and 9.0. LaBatea does not compile with gcc-4.1.0 or older. The quickbook generated documentation is included in the zip files and is also available online at http://herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/index.html Sources are also available form the sandbox: https://svn.boost.org/svn/boost/sandbox/itl/ To close my request for review, let me take the opportunity to do some advertisement ;-) focusing on some of the itl's highlights. * The Itl emerged out of real world software development extracting generic functionality from numerous use cases of the date time problem domain. (http://www.herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/boost_itl/ex…) But the need for the same data structures occurs in other fields as well. E.g. Zachary Turner uses a compressed_bitmap similar to an itl::interval_set to manage very large file system allocation bitmaps and gives more use cases here (http://lists.boost.org/Archives/boost/2009/06/152817.php) * Aggregation on overlap not only provides a useful feature to compute aggregation results on interval_maps like statistics, it also leads to a generalized addition operation on maps that exhibits interesting semantical properties. E.g. (http://herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/boost_itl/semant…) * The itl's design is based on sets of laws (aka axioms) that are described in the documentation. (http://herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/boost_itl/semant…) These law sets not only are giving a formal specification of the library. Using the law based testing tool (LaBatea) (https://svn.boost.org/svn/boost/sandbox/itl/boost/validate) allows to validate the library code for every specified law. * For the itl, 18 laws have been validated on the 7 container templates with varying instantiation types for template parameters, running a total of 719 different law instances (each of them for large numbers of randomly generated test data). (https://svn.boost.org/svn/boost/sandbox/itl/libs/validate/example/) This gives everyone a method to check semantical properties of the library in a way that is more powerful than traditional unit tests. To get the 'complete picture' of the library's interface you may want to refer to the synoptic function table first (http://www.herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/boost_itl/in…) before looking at more specific topics. Hoping to have quickened your appetite to take a closer look at this library before and during the review process. best regards Joachim Faulhaber

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[task]
by Baxter Jeremy 03 Oct '09

03 Oct '09

I have been looking at the boost task library from the vault and comparing it with the threadpools library http://threadpool.sourceforge.net and have a few comments. Firstly I should say that I'm interested in tasks / thread pools for a situation rather different from the one for which they are designed. Namely the case in which threads (tasks) are being used to monitor some internal or external activities and so may block for significant periods of time waiting for the result of a complex planning algorithm or for some condition being met. I'm therefore worried about blocking all the available threads. I think what I need is to be able to dynamically add new threads to the thread pool, or just not use a pool at all and create and destroy a thread for every subtask. However during my review I came across a helper function which I though might allow re-use of the same thread but I'm concerned could actually lead to deadlock: reschedule_until <file:///D:\Boost\boost.task-0.3.0\doc\html\boost_task\utilities.html> In the function boost::this_task::reschedule_until( Pred const&) allows to synchronize the task with other asynchronous events without blocking the worker-threads (bool Pred::operator()() must not block). The current task will be rescheduled until the passed predicate becomes true. Looking at the code I don't think this is an accurate description and gives the potential to introduce deadlocks in tasks which otherwise would operate normally. >From the code what reschedule_until does is repeatedly call the process_ function to look for new tasks, testing once each task has finished to see if the predicate has been met. This is not quite as described since the task is not 're-scheduled' it is actually blocked until whatever task the scheduler next selects is complete. This introduces problems if multiple tasks on the queue use reschedule_until. If there are three tasks T1 T2 and T3 on the queue doing the following: T1 { ... Reschedule_until(A) B.setTrue() ... } T2 { ... Reschedule_until(B) ... } T3 { ... A.setTrue() } What we would like to happen, and what will happen if they are run in different threads (or a different order on the one thread) is that T1 does some work, waits for T3 then terminates. T2 does some work, waits for T1, then does some more work. T3 independently does its work and finishes by signalling that T1 can continue. Unfortunately if they are scheduled in the order T1 T2 T3 then T1 runs, reschedules and T2 gets to run until it reschedules and T3 gets to run. When T3 finishes T1 is in a position when it can run, however it will not get the chance to because in order for condition A to be checked T2 has to have finished, and it can't do that until B is set true. Therefore although progression should be possible as the condition T1 is waiting for has been met it will never notice and T1 and T2 will never complete. I'm not sure that there is a general solution to this problem without using more threads so that any potentially runnable task will get a chance. A second comment. Comparing the task and thread pool libraries they use different waiting mechanisms. Thread pool uses a wait-notify construct on the queue to block worker threads if the queue is empty. Task uses active polling, trying to get items from the queue and then sleeping for a short period if nothing can be found on the queue. I wondered why the difference is there. Wait - notify would look like it should perform better in the case where there are fewer tasks than threads is polling better in the case where there are many more tasks than threads and so threads will never sit idle polling for long? Jeremy Jeremy Baxter Lead Researcher, UAVs & Autonomy Tel: 01684 894801 email: jwbaxter(a)QinetiQ.com www.QinetiQ.com QinetiQ - Delivering customer focused solutions Please consider the environment before printing this email. The information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). The information in this communication may be confidential and/or legally privileged. Nothing in this e-mail is intended to conclude a contract on behalf of QinetiQ or make QinetiQ subject to any other legally binding commitments, unless the e-mail contains an express statement to the contrary or incorporates a formal Purchase Order. 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[utility] Fix for const issue of value_initialized merged to release
by Niels Dekker - address until 2010-10-10 03 Oct '09

03 Oct '09

FYI, I have just merged the fix of ticket #2548, regarding value_initialized, to the release branch. The fix has been on the trunk for quite a few months, and Fernando Cacciola has told me he thinks that it's okay to merge it. The fix disables implicit conversion from const value_initialized<T> to non-const T&. More information: Ticket #2548, Let's fix the logical constness of value_initialized!" https://svn.boost.org/trac/boost/ticket/2548 [boost] [utility] A fix for the const issue of value_initialized http://lists.boost.org/Archives/boost/2009/02/148489.php Changeset 56547: Merged value_init from the trunk, including fix of #2548, regarding "const value_initialized" https://svn.boost.org/trac/boost/changeset/56547 Kind regards, Niels -- Niels Dekker http://www.xs4all.nl/~nd/dekkerware Scientific programmer at LKEB, Leiden University Medical Center

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[Serialization] Question about "Back versionning"
by Vincent Thomas 02 Oct '09

02 Oct '09

Hi, During some testing of boost::serialization features, I tried to do this : Let's say we have a class X, the current version for this class is 5 (BOOST_CLASS_VERSION(X, 5)). Serialize in class X is split into save/load.What I'd like to do now, is save an object of type X at version 3 to make the object loadable by an older version of my software. that is get ""<X class_id="0" tracking_level="0" version="3">" in my resulting file instead of "<X class_id="0" tracking_level="0" version="5">". I've gone through the documentation of boost::serialization and I found only one thing. A TODO speaking about "Back versionning". It's not clear for me if this part speaks about the archive (like xml_oarchive, xml_iarchive, ...) or the object I can serialize, in other words does it concern this line "<boost_serialization signature="serialization::archive" version="5">" or a line like this one "<test class_id="0" tracking_level="0" version="2">" in a resulting file ? Maybe it concerns both but that I don't know. So apparently If I understand the documentation correctly I can't do what I describe above at the moment. Does anyone know if it's going to be implemented soon, or if I can be of any help ? Vincent

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Hello and a quick question.
by S. Brad Daughdrill 02 Oct '09

02 Oct '09

Hello to all, I first want to say hello to all the members. I recently ran across your project, and I am really interested in working with you all. My question is are there an example that use forms? The example I found all seem to be console applications and while they are helpful, I really want my students to start programming with forms (initially at least). They will be using Visual C++ 2008 Express. Thank you for everything ahead of time. Brad *----- S. Brad Daughdrill The University of Alabama B.S. Management Information Systems M.S. Operations/Project Management M.B.A. Financial Risk M.A. Economics (Candidate) 146 Lenora Drive Tuscaloosa, AL 35401 (o) 205.348.7591, Bidgood Hall - 351E (c) 251.510.3089 (e) S.Brad.Daughdrill(a)Gmail.com*

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threads: how to remotely kill a thread?
by David M. Cotter 02 Oct '09

02 Oct '09

say i'm on the main thread, and i've got a thread::id of some other preemptive thread. i do not have the actual boost::thread object any more. and i want to unceremoniously kill that thread. like right now. how do i kill it? i don't see a way to recover the actual boost::thread from the thread::id. but even if i could, and then call thread.interrupt(), that's more of a polite request which is free to be ignored, rather than a you_must_die_now() thing.

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[BGL] Why source() needs a graph argument?
by Cosimo Calabrese 02 Oct '09

02 Oct '09

Hi to all, the question is in subject. I don't understand it. Either source() and target() functions only return the m_source member and the m_target of edge_base. They don't use the graph argument, that is not even used. I need to know it because I'm implementing an union_graph adaptor, that provides the join's view of 2 graph. When I call the source() function on a union_graph, I provide an edge_descriptor; but whereas the source() function of an adjacency_list needs a graph argument, I need to know which graph belongs the edge, which is an 2 * O|E| operation on 2 graphs. Thanks, Cosimo Calabrese

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