- Boost - lists.preview.boost.org

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

4 5

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.

4 4

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).

2 1

[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

1 0

[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

6 11

[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

3 23

[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

1 0

[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

3 4

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