May 2011 - Boost - lists.preview.boost.org

Boost.Conversion: functors namming
by Vicente BOTET 25 May '11

25 May '11

Hi, during the Boost.Convert after review discussion there were some proposals to use Boost.Phoenix to build the functors. My question is what should be the name of the function that builds the functor. Some possibilities: short s=1; long l=3; using boost::phoenix::placeholders::_1; A- Use a different name: make_converter_to? s=boost::make_converter_to(*short*)(_1)(l) ; B- Use the same name in a different namespace. What about using "fp" as namespace (functional programming). s=boost::conversion::fp::convert_to(*short*)(_1)(l) ; C- Use the same name in the same namespace and use SFINAE/enable_if to select the correct implementation depending on the parameter. s=boost::convert_to(*short*)(_1)(l) ; Which are your preferences? Best, Vicente

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[type traits] issue with operator traits and volatile qualifier
by Frédéric Bron 25 May '11

25 May '11

Sorry for being absent during the last month but it was very hard to find any time to work on the addition of the operator traits. I have not yet had the time to deal with the naming issue... But I found something more tricky while trying to solve the issue of reference types (& was just ignored). I never used the volatile qualifier but I found that the following behaviour breaks the code that detects if an operator returns void or not. Could someone tell me why the following code does not compile? bool f() { } void g(const volatile bool &) { } int main() { g(f()); return 0; } Many thanks, Frédéric

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Re: [boost] [Lambda] Handling Bind/Lambda name clashes.
by Max Sobolev 25 May '11

25 May '11

On 25.05.2011 15:49, Eric Niebler wrote: > (fixing attribution...) > > On 5/23/2011 11:42 PM, Robert Jones wrote: >> On Thu, Apr 7, 2011 at 3:01 PM, Steven Watanabe wrote: >>> At some point in time, Eric Niebler wrote: >>>> And what is wrong with leaving bind in the boost namespace as I was >>>> suggesting and define boost::function like this: >>>> >>>> namespace boost { >>>> namespace function_adl_block { >>>> template<class Sig> >>>> struct function {...}; >>>> } >>>> using function_adl_block::function; >>>> } >>>> >>>> Now the "boost" namespace is no longer associated with >>>> boost::function, >>>> and boost::bind won't be found by ADL. > > It's probably a good general policy to move most/all types in Boost into > ADL-blocking namespaces like above, except those for which there is > reason to keep boost as an associated namespace. cool technique (for building more modular software / libs)!

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[chrono, trunk] linux compile fix
by Tim Blechmann 25 May '11

25 May '11

today's trunk does not compile correctly. this trivial patch fixes the issue: thanks, tim Index: boost/chrono/detail/inlined/posix/thread_clock.hpp =================================================================== --- boost/chrono/detail/inlined/posix/thread_clock.hpp (revision 72154) +++ boost/chrono/detail/inlined/posix/thread_clock.hpp (working copy) @@ -21,6 +21,7 @@ thread_clock::time_point thread_clock::now( ) { + struct timespec ts; #if defined CLOCK_THREAD_CPUTIME_ID // get the timespec associated to the thread clock if ( ::clock_gettime( CLOCK_THREAD_CPUTIME_ID, &ts ) ) @@ -31,7 +32,6 @@ clockid_t clock_id; pthread_getcpuclockid(pth, &clock_id); // get the timespec associated to the thread clock - struct timespec ts; if ( ::clock_gettime( clock_id, &ts ) ) #endif { @@ -49,6 +49,7 @@ } thread_clock::time_point thread_clock::now( system::error_code & ec ) { + struct timespec ts; #if defined CLOCK_THREAD_CPUTIME_ID // get the timespec associated to the thread clock if ( ::clock_gettime( CLOCK_THREAD_CPUTIME_ID, &ts ) ) @@ -59,7 +60,6 @@ clockid_t clock_id; pthread_getcpuclockid(pth, &clock_id); // get the timespec associated to the thread clock - struct timespec ts; if ( ::clock_gettime( clock_id, &ts ) ) #endif {

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Re: [boost] [pre-review] Pimpl submission in the review queue
by Sean Chittenden 25 May '11

25 May '11

> I have a Pimpl generalization submission getting close to the top in the review > queue. Rob Stewart suggested I'd post it to the new Boost Code Collaborator site > for a pre-review. That's what I did with the following link to the pre-review > (Review #5): > > http://demo.smartbear.com/boost/go?page=ReviewDisplay&reviewid=5 > > Your participation in that pre-review is most welcome. Fantastic! I signed up and am anxious to see this library accepte^Wreviewed^Waccepted. I've been using the Boost.Pimpl interface for nearly a year now and have been very successful and happy with its use in my projects. Second to ASIO, Boost.Pimpl has done more to impact the design, structure and maintenance of my projects than any other library (the benefits of a stable ABI are understated). Its use in maintaining clean interfaces and projects can't be understated. Historically I'd always saved implementing Pimpl for external facing bits and had always rolled my own interface, now I use it for everything internal or external because of how easy it is to thump out a Boost.Pimpl based interface. As I said on the review site, I've moved the Pimpl implementation in to "boost/pimpl" directory with success, though was not able to move the Pimpl library under the boost namespace. Actually... let me post a quick example that I wrote to both learn and quickly teach how to use Pimpl: https://github.com/sean-/Boost.Examples/tree/master/pimpl It takes about 60sec-3min for most people to have their "ah ha!" moment with that example (those unfamiliar with Pimpl would be wise to check it out, imnsho). I didn't dive in to the why, but in the implementation it is necessary open your namespace after you have defined your private implementation (see pimpl/pimpl_example_pointer_impl.cc:35). It would be nice to know why this is the case (or if it's a bug). Pre-review feedback: The examples used in the Pimpl unit tests are very very good, but it takes a few minutes to wade through the polymorphism and to tease out the most basic requirements for starting to use Pimpl. Walking through 1K of code to do something very simple is a bit daunting despite the obvious and nearly immediate dividends. Whenever I started using this, it was one of the best few hours I've ever spent learning something new. I'm very pleased to see this library move forward and look forward to its formal review. -sc -- Sean Chittenden sean(a)chittenden.org

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Re: [boost] [date_time] Time zone improvements
by Rutger ter Borg 25 May '11

25 May '11

Jeff Garland wrote: > Very cool :-) One question -- is there a portable solution where a user > could deploy a files onto a Windows system or is it a Unix only solution? > I'm fine with incorporating a *nix only solution because what your > suggesting will be a nice solution for *nix platforms, but it will need to > be clear that it's not portable. I don't see why it wouldn't be possible to deploy the (big-endian) binary files to any platform. Getting it into this binary form (using zone info compiler zic) may be harder to do cross-platform, but cygwin may help here. [snip] > As the primary maintainer of Boost date-time I can say with certainty that > there is interest in this functionality -- it's long been on my todo list > and I haven't had time to get to it. You can email me privately and we > can discuss all the details of how to get your code incorporated. I'll do! Regards, Rutger

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Re: [boost] [ICL] some improvement proposals
by Joachim Faulhaber 25 May '11

25 May '11

Hi Denis, thanks for your input again. You're a good analyzer of code. Maybe you want to consider writing a code review for libraries that are submitted for formal review on the boost developer's list from time to time :) 2011/5/19 Denis <denis(a)camfex.cz>: > Hi > > 1. (questionable because it changes the visible interface): rename > `left_open` and `right_open` to `right_closed` and `left_closed`. > > Reason: interval_bounds is used in bitwise operations with bit=1 means > `closed`. (1) I tried to consider common usage of naming of intervals that is known from math. There seems to tendency to assume closedness as default, while openness is indicated by naming: [x, y] an interval (also closed interval) [x, y) a right open interval (x, y] a left open interval (x, y) an open interval. (2) The bits are chosen so closedness is indicated by 1 and openness is indicated by 0 11 [x, y] an interval (also closed interval) 10 [x, y) a right open interval 01 (x, y] a left open interval 00 (x, y) an open interval. > `left_closed() | open()` resulting in `left_closed()` is more readable than > `right_open() | open()` resulting in `left_closed()`. > > Also, there are checkers `is_left_closed()` and `is_right_closed()` but not > for *_open ... again following common usage [see (1)]. > I had to use `class bounded_value` in my program (as in Icl details: > calculating lower and upper bound of interval separately, then constructing > the interval, bitwise or'ing bounds) > and I commented every usage of `right_open()` as `left closed` in order to > explain why I use `interval_bounds::right_open()` in constructing the left > `bounded_value` of the interval. > This resulted in the idea of renaming. > > Maybe making bit=1 mean `open` would be less painful for other users ? You see me inconsolable to hear that you are suffering pain from my library =( There is an concept "interval_bound" http://svn.boost.org/svn/boost/trunk/boost/icl/concept/interval_bounds.hpp that allows you to combine and-ing or-ing etc. of interval_bounds directly. I think that'll reduce your suffering, at least I hope so. Yes, it's missing from the docs. Would you create a ticket? BTW, you may locally extend the concepts in the way you desire and add functions according to you naming rational. > 2. define `contains(interval, elt)` as `!below(interval, elt) && > !above(interval, elt)` allowing the user to use `below()` and `above()`. > Sometimes it is useful. (3) Thanks for this suggestion. The design of the icl::interval's interface is done under the general requirement of minimality. The concept approach allows you always to add own function templates locally to the concept if you need them. > Anyway, all the versions of `contains()` are made of checking for both > bounds. If you found a suboptimal function implementation, please refer them specifically. I'd appreciate a suggestion for an optimization. You can also create a ticket. > 3. It would nice if the functions taking two intervals will have versions > taking an element as second argument. > I mean functions like `left_subtract`, `operator &`, etc. (I cannot tell all > the list at the moment) > Constructing temporary `close_interval` object in order only to pass it into > those functions is cheap with ints but would be expensive with > heap-allocated domains (blobs, strings, etc). This is worth considering. In my own use of intervals within the implementation of interval containers I never encountered the need for such functions ... yet they may be useful in other situations. What do others think? Best regards, Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

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[Iterator] Constness of transform_iterator's dereference operator
by Michel MORIN 24 May '11

24 May '11

(In the previous mail, "function call operator" should be "dereference operator". Sorry for this, I fix it and resend a mail.) A long-standing request that transform_iterator should use boost::result_of will be resolved in Boost 1.47. This is really nice news, but I have a concern related to this. In the new code, transform_iterator uses result_of<UnaryFunc(typename std::iterator_traits<Iterator>::reference)> to determine the return type of a functor. However, since transform_iterator's dereference operator is const, result_of<const UnaryFunc(typename std::iterator_traits<Iterator>::reference)> should be used instead. There is a patch for this fix in #5127: https://svn.boost.org/trac/boost/ticket/5127 Alternatively, to remove this inconsistency, we can strip the constness of transform_iterator's dereference operator by either A. Make UnaryFunc member data mutable as suggested in #4969: https://svn.boost.org/trac/boost/ticket/4969 or B. Add non-const overloads to - transform_iterator's dereference() function - iterator_core_access' dereference() function - iterator_facade's operator*() Patches for A (make_mutable.patch) and B (add_nonconst_overloads.patch) are attached in this mail. Comments? Regards, Michel

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Re: [boost] [pre-review] Pimpl submission in the review queue
by Jeff Garland 24 May '11

24 May '11

Mostafa wrote: >> If you want to use the Code Collaborator site to examine the library, you must create an account. The good news is that there are other libraries there that you can review, too. If you wish to avoid creating an account, then you can follow the link on the review schedule to the code in the sandbox. > > Some may just want to follow a review without necessary participating in one. Requiring a user account discourages such activity, and in my opinion, creates an artificial barrier to further engagement between newcomers, or even existing Boost watchers, and Boost, even if it is a one-sided engagement. > > My thoughts, > > Mostafa This is all getting a bit ahead of my post-boostcon report on the library in a week review activities, but to answer this particular issue I'd say 1) you need a login to participate in the mailing list, 2) it's essential for spam prevention, and 3) data can be periodically put to the list to mitigate this issue. Below is a report (minor formatting tweaks) of the pimpl review generated from code collaborator. I think in all likelihood using one of the modern review tools is going to create a better environment overall. Jeff ************* Overview ID: 5 Status: Inspection Title: Pimpl idiom generalization. Creator: Vladimir Batov Created On: 2011-05-23 15:13 Finished On: 2011-05-24 11:55 Total Person Time: 01:27:06 Wall-Clock Time: 20:34:38 Total Reviewer Time: 00:46:00 LOC All Versions (Uploaded/Changed): 2997/0 LOC Final Versions (Uploaded/Changed): 2997/0 Document Pages (All): 0 Document Pages (Final): 0 Number of Defects: 16 Number of Comments: 8 ************* Overview: Support for value and pointer semantics. Support for boost::serialization. Support for separate -- interface and implementation -- class hierarchies (the Bridge pattern in GoF). Support for internal (implementation-only) run-time polymorphism (Non-Virtual Interface Idiom). Support for delegating constructors. Tutorial. Doxygen-generated docs. Linux and VS2008. ************* Participants Name Role Person-Hours Vladimir Batov Author 00:13:17 Robert Stewart Reviewer 00:46:00 Sean Chittenden Observer 00:06:13 ************* Defect Log ID Creator File Location Type Severity Text D22 Robert Stewart pimpl.hpp Line 25 Interface Major Names with two consecutive underscores are reserved for the implementation D23 Robert Stewart pimpl.hpp Line 25 Style Minor This macro name should start with "BOOST_PIMPL_" D24 Robert Stewart pimpl.hpp Line 54 Interface Minor pimpl<T>::xxxx_semantics is interesting, but xxxx_pimpl<T> is simpler and more direct. D25 Robert Stewart pimpl.hpp Line 157 Interface Major Names with double underscores are reserved for the implementation D26 Robert Stewart pimpl.hpp Line 158 Interface Major Names with double underscores are reserved for the implementation D27 Robert Stewart pimpl.hpp Line 159 Interface Major Names with double underscores are reserved for the implementation D28 Robert Stewart pimpl.hpp Line 160 Interface Major Names with double underscores are reserved for the implementation D29 Robert Stewart pimpl.hpp Line 244 Interface Major Names with double underscores are reserved for the implementation D30 Robert Stewart pimpl.hpp Line 49 Interface Minor What about Pimpl support for classes with a base class? Your design requires multiple inheritance. You could, instead, do the following: class Book : public value_pimpl<Book, Base> { }; template <class T, class Base = null_type> class value_pimpl : public Base { }; template <class T> class value_pimpl<T,null_type> { }; D31 Robert Stewart pimpl.hpp Line 291 Interface Minor This exposes too much of the implementation to the user. A construct() member function set, like the set of constructors your macro now generates, with perfect forwarding (and variadic support, when available), would be better. construct() can call the new operator and save the pointer, thereby hiding those details from the user. D32 Robert Stewart pimpl.hpp Line 57 Interface Minor This exposes the pseudo-smart pointer semantics. It shouldn't be public and it should probably be named "nil" rather than "null." The idea is that nil() returns an object with no implementation rather than a null pointer. D33 Robert Stewart pimpl-use-cases.html Line 346 Documentation Minor "It is not but not a 100% kosher" is nonsensical. Presumably, you mean something like, "This design has some problems." D35 Robert Stewart pimpl-use-cases.html Line 357 Documentation Minor s/nut shell/nutshell/ D36 Robert Stewart pimpl-use-cases.html Line 364 Documentation Minor s/More,/What's more,/ D37 Robert Stewart pimpl-use-cases.html Line 385 Documentation Minor s/for vast majority/for the vast majority/ D38 Robert Stewart pimpl-use-cases.html Line 386 Documentation Minor You can avoid the subsequent "he/she" awkwardness by rephrasing this sentence: "However, putting both book1 and book2 in a std::set results in two elements rather than one, despite the fact that they are supposed to represent the same Book." Overall Review Conversation Sean Chittenden I've been using Boost.Pimpl for almost a year now with great success (using it in conjunction with MSM, ASIO and Spirit). This has been an incredibly useful library for minimizing the interfaces exposed across components. There are three things that I'd like to see but are largely trivial: 1) a set of clean-room examples of the two implementations (i.e. split out the unit tests from a set of examples for pointer and value semantics), and an example of how to use Pimpl once it has been moved in to the boost namespace (I took a crack at this and was never successful at moving Pimpl in to the boost namespace).

1 0

Implicit cast rules
by Gregory Crosswhite 24 May '11

24 May '11

Hey everyone, Would someone please explain to me the implicit cast rule that prevents the following from compiling, and/or if there is a way around it? #include <boost/optional.hpp> #include <iostream> using namespace boost; using namespace std; struct C { operator optional<int>() { return none; } }; int main() { C c; cout << static_cast<optional<int> >(c) << endl; return 0; } Error message: In file included from /usr/include/boost/optional.hpp:15, from cast-to-optional.cpp:1: /usr/include/boost/optional/optional.hpp: In member function ‘void boost::optional_detail::optional_base<T>::construct(const Expr&, const void*) [with Expr = C, T = int]’: /usr/include/boost/optional/optional.hpp:262: instantiated from ‘boost::optional_detail::optional_base<T>::optional_base(const Expr&, const Expr*) [with Expr = C, T = int]’ /usr/include/boost/optional/optional.hpp:559: instantiated from ‘boost::optional<T>::optional(const Expr&) [with Expr = C, T = int]’ cast-to-optional.cpp:13: instantiated from here /usr/include/boost/optional/optional.hpp:392: error: cannot convert ‘const C’ to ‘int’ in initialization I can tell what is happening; it would seem that the implicit cast rule selects the optional() constructor before it even looks at my more specific cast operator. I'm just confused about why this should be, since I see no reason why constructor casts should be prioritized over operator casts. Is this just the way it is, a GCC quirk, something I'm doing wrong, etc? Thanks! Greg

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Towards a plan to reduce active tickets
by Vicente BOTET 24 May '11

24 May '11

Hi, I've inspected the number of tickets since the las Bug Sprint and we ca see that we are having a mean of 18 additional active tickets each month. month created closed diff 01/05/10 99 107 8 01/06/10 122 316 194 // Bug Sprint 01/07/10 103 56 -47 01/08/10 115 120 5 01/09/10 85 34 -51 01/10/10 105 91 -14 01/11/10 109 80 -29 01/12/10 83 92 9 01/01/11 98 79 -19 01/02/11 98 71 -27 01/03/11 161 107 -54 01/04/11 105 145 40 MEAN 106,2 87,5 -18,7 * MEAN is calculated since the last Bug Sprint, that is for the last 10 months. I don't know what could be done to instead of having more active tickets each month having less. While the Bug Sprints are useful I think that we need to have a plan to reduce them is a regular way. I know that a lot of people would be at BoostCon. It would be great if this subject could be discussed in one of the general sessions. if you have any suggestion, please replay to this post and share your view with the Boost community. Best, Vicente

7 7

[Iterator] Constness of transform_iterator's function call operator
by Michel MORIN 24 May '11

24 May '11

A long-standing request that transform_iterator should use boost::result_of will be resolved in Boost 1.47. This is really nice news, but I have a concern related to this. In the new code, transform_iterator uses result_of<UnaryFunc(typename std::iterator_traits<Iterator>::reference)> to determine the return type of a functor. However, since transform_iterator's function call operator is const, result_of<const UnaryFunc(typename std::iterator_traits<Iterator>::reference)> should be used instead. There is a patch for this fix in #5127: https://svn.boost.org/trac/boost/ticket/5127 Alternatively, to remove this inconsistency, we can strip the constness of transform_iterator's function call operator by either A. Make UnaryFunc member data mutable as suggested in #4969: https://svn.boost.org/trac/boost/ticket/4969 or B. Add non-const overloads to - transform_iterator's dereference - iterator_core_access' dereference - iterator_facade's operator() Patches for A (make_mutable.patch) and B (add_nonconst_overloads.patch) are attached in this mail. Comments? Regards, Michel

1 0

BoostCon 2011 in German IT news
by Boris Schaeling 24 May '11

24 May '11

I got BoostCon 2011 into the German IT news on http://www.heise.de/developer/artikel/developer_artikel_1247894.html. If someone wants to contact IT websites in other countries (after all as a C++ developer I want to read about things like BoostCon), have a look at the article. This should give you an idea how you could get in contact with websites and provide them the kind of news they want to publish. As the conference ended last week, it maybe makes sense to send out "press articles" again when the videos of the presentations are online. Boris

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How to determine if a function with a given signature is declared?
by andrew.beck＠astc-design.com 24 May '11

24 May '11

Hi, Newbie question follows... I've used BOOST_MPL_HAS_XXX_TRAIT_DEF in the past but recently needed to determine if a function was defined with a given signature. Searching boost::mpl, stackoverflow etc, I couldn't find anything to do what I needed. I've attached my solution below. Basically, I'm wondering if there is a boost::mpl solution or some other more elegant solution. thanks, andrew #include <boost/mpl/bool.hpp> #include <boost/mpl/assert.hpp> #define XXX_DEFINED(symbol) \ template <typename T, T* = symbol> \ struct check_ ## symbol \ { \ typedef void type; \ }; \ \ template <typename T, typename enable = void> \ struct symbol ## _defined : \ boost::mpl::false_ \ { }; \ \ template <typename T> \ struct symbol ## _defined<T, typename check_ ## symbol<T>::type > : \ boost::mpl::true_ \ { }; // declare a some_func(int) so we can see if its declared... void some_func(int) {} // defines some_func_defined template XXX_DEFINED(some_func); BOOST_MPL_ASSERT(( some_func_defined<void(int)> )); // some_func(double) hasn't been declared BOOST_MPL_ASSERT_NOT(( some_func_defined<void(double)> ));

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[function] Problem copying when constructed with a functor
by Edward Diener 24 May '11

24 May '11

This simple code: #include <boost/detail/lightweight_test.hpp> #include <boost/function.hpp> struct p_functor_class_int { p_functor_class_int() : data(50) { } int operator()() const { return data; } void operator()(int d) { data = d; } int data; }; int main() { boost::function<int ()> bfun(p_functor_class_int()); boost::function<int ()> bfun2(bfun); return boost::report_errors(); } gives compiler errors. On gcc-4.6 I get: "In file included from C:\Programming\VersionControl\boost/boost/function/detail/maybe_include.hpp:13:0, from C:\Programming\VersionControl\boost/boost/function/detail/function_iterate.hpp:14, from C:\Programming\VersionControl\boost/boost/preprocessor/iteration/detail/iter/forward1.hpp:47, from C:\Programming\VersionControl\boost/boost/function.hpp:64, from test_function_bug.cpp:2: C:\Programming\VersionControl\boost/boost/function/function_template.hpp: In static member function 'static R boost::detail::function::function_invoker0<FunctionPtr, R>::invoke(boost::detail::function::function_buffer&) [with FunctionPtr = boost::function<int()> (*)(p_functor_class_int (*)()), R = int]': C:\Programming\VersionControl\boost/boost/function/function_template.hpp:907:60: instantiated from 'void boost::function0<R>::assign_to(Functor) [with Functor = boost::function<int()> (*)(p_functor_class_int (*)()), R = int]' C:\Programming\VersionControl\boost/boost/function/function_template.hpp:722:7: instantiated from 'boost::function0<R>::function0(Functor, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type) [with Functor = boost::function<int()> (*)(p_functor_class_int (*)()), R = int, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type = int]' C:\Programming\VersionControl\boost/boost/function/function_template.hpp:1042:16: instantiated from 'boost::function<R()>::function(Functor, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type) [with Functor = boost::function<int()> (*)(p_functor_class_int (*)()), R = int, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type = int]' test_function_bug.cpp:15:37: instantiated from here C:\Programming\VersionControl\boost/boost/function/function_template.hpp:95:39: error: too few arguments to function C:\Programming\VersionControl\boost/boost/function/function_template.hpp:96:9: warning: control reaches end of non-void function [-Wreturn-type] " I am sure I must be doing something wrong but I can not see it.

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Review Wizard Report for May 2011
by Ronald Garcia 23 May '11

23 May '11

============================================== Review Wizard Status Report for May 2011 ============================================== News ==== 1. Process Library Rejected 2. Phoenix Library Accepted 3. XInt Library Rejected 4. Type Traits Extensions Accepted 5. Locale Library Accepted 6. Convert Library Withdrawn 7. Conversion Library Accepted Provisionally 8. Context Library Accepted Provisionally 9. Boost 1.46.1 Released Revised Libraries: Asio, Filesystem, Fusion, Graph, ICL, Math, Polygon, Proto, Property Tree, Signals2, TR1, Unordered Revised Tools: Quickbook Open Issues =========== The following libraries have been reviewed and await reports from their review managers: * AutoIndex(Tool) - reviewed May 2011; review manager: Daniel James. The following libraries have been accepted to Boost, but have not yet been submitted to SVN: * GIL.IO - accepted January 2011; author: Christian Henning. * Type Traits Extensions - accepted March 2011; author: Frederic Bron. The following libraries have been accepted and submitted to SVN, but have not yet appeared in a release: * Phoenix - accepted March 2011; author: Joel de Guzmann. * Move - accepted February 2011; author: Ion Gaztanaga. * Geometry Library - accepted November 2009; author: Barend Gehreis et al. * Ratio - accepted October 2010; author: Vicente Botet. * Chrono - accepted January 2011; author: Vicente Botet. The following libraries have been accepted provisionally to Boost, but have not been submitted for mini-review and full acceptance: * Switch - accepted provisionally January 2008; author: Steven Watanabe. * Log - accepted provisionally March 2010; author: Andrey Semashev. * Context - accepted provisionally May 2011; author: Oliver Kowalke. General Announcements ===================== As always, we need experienced review managers. The review schedule has grown substantially but we have few volunteers, so manage reviews if possible and if not please make sure to watch the review schedule and participate. Please take a look at the list of libraries in need of managers and check out their descriptions. In general review managers are active boost participants, including library contributors, infrastructure contributors, and other mailing list participants with a substantial track record of constructive participation. If you can serve as review manager for any of them, email Ron Garcia or John Phillips, "rxg at cs dot cmu dot edu" and "phillips at pacific dot mps dot ohio-state dot edu" respectively. We are also suffering from a lack of reviewers. While we all understand time pressures and the need to complete paying work, the strength of Boost is based on the detailed and informed reviews submitted by you. If you are interested in reviewing a library but won't have time during the review period, you can always prepare your review ahead of time. No rule says you can only work on a review during the review period. A link to this report will be posted to www.boost.org. If you would like us to make any modifications or additions to this report before we do that, please email Ron or John. The review schedule is an unordered list of the libraries awaiting review. As such, any library on the schedule can be reviewed once the developer is ready, a review manager has been secured, and the manager, developer, and wizards agree on a date to schedule the review. Review Schedule =============== * Join (M) * Pimpl (M) * Endian * Conversion * Sorting (M) * AutoBuffer * Containers * Lockfree * Fiber (M) * Quaternions, Vectors, Matrices (M) * Stopwatches * Variadic Macro Data (M) * Type Traits Introspection * Block Pointer (M) * Heaps * Assign v2 * Network (M) * Algorithm * Local (M) ``(M)`` marks libraries that need review managers. -------------------- Join ---- :Author: Yigong Liu :Review Manager: Needed :Download: http://channel.sourceforge.net/ :Description: Join is an asynchronous, message based C++ concurrency library based on join calculus. It is applicable both to multi-threaded applications and to the orchestration of asynchronous, event-based applications. It follows Comega's design and implementation and builds with Boost facilities. It provides a high level concurrency API with asynchronous methods, synchronous methods, and chords which are "join-patterns" defining the synchronization, asynchrony, and concurrency. Pimpl ----- :Author: Vladimir Batov :Review Manager: Needed :Download: | `Boost Vault <http://www.boost-consulting.com/vault/index.php?action=downloadfile&fil…>`__ | http://www.ddj.com/cpp/205918714 (documentation) :Description: The Pimpl idiom is a simple yet robust technique to minimize coupling via the separation of interface and implementation and then implementation hiding. This library provides a convenient yet flexible and generic deployment technique for the Pimpl idiom. It's seemingly complete and broadly applicable, yet minimal, simple and pleasant to use. Endian ------ :Author: Beman Dawes :Review Manager: Joel Falcou :Download: http://svn.boost.org/svn/boost/sandbox/endian/ :Description: Conversion ---------- :Author: Vicente Botet :Review Manager: Gordon Woodhull :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=co…>`__ :Description: Generic explicit conversion between unrelated types. Boost.Conversion provides: * a generic ``convert_to`` function which can be specialized by the user to make explicit conversion between unrelated types. * a generic ``assign_to`` function which can be specialized by the user to make explicit assignation between unrelated types. * conversion between ``std::complex`` of explicitly convertible types. * conversion between ``std::pair`` of explicitly convertible types. * conversion between ``boost::optional`` of explicitly convertible types. * conversion between ``boost::rational`` of explicitly convertible types. * conversion between ``boost::interval`` of explicitly convertible types. * conversion between ``boost::chrono::time_point`` and ``boost::ptime``. * conversion between ``boost::chrono::duration`` and ``boost::time_duration``. Sorting ------- :Author: Steven Ross :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=al…>`__ :Description: A grouping of 3 templated hybrid radix/comparison-based sorting algorithms that provide superior worst-case and average-case performance to std::sort: integer_sort, which sorts fixed-size data types that support a rightshift (default of >>) and a comparison (default of <) operator. float_sort, which sorts standard floating-point numbers by safely casting them to integers. string_sort, which sorts variable-length data types, and is optimized for 8-bit character strings. All 3 algorithms have O(n(k/s + s)) runtime where k is the number of bits in the data type and s is a constant, and limited memory overhead (in the kB for realistic inputs). In testing, integer_sort varies from 35% faster to 2X as fast as std::sort, depending on processor, compiler optimizations, and data distribution. float_sort is roughly 70% faster than std::sort. string_sort is roughly 2X as fast as std::sort. AutoBuffer ---------- :Author: Thorsten Ottosen :Review Manager: Robert Stewart :Download: http://www.cs.aau.dk/~nesotto/boost/auto_buffer.zip :Description: Boost.AutoBuffer provides a container for efficient dynamic, local buffers. Furthermore, the container may be used as an alternative to std::vector, offering greater flexibility and sometimes better performance. Containers ---------- :Author: Ion Gaztanaga :Review Manager: John Maddock :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bo…>`__ :Documentation: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/move/libs/container/doc/html/index.h…>`__ :Description: Boost.Container library implements several well-known containers, including STL containers. The aim of the library is to offers advanced features not present in standard containers or to offer the latest standard draft features for compilers that comply with C++03. Lockfree ------------------ :Author: Tim Blechmann :Review Manager: Hartmut Kaiser :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bo…>`__ :Documentation: http://tim.klingt.org/boost_lockfree/ :Description: Lockfree provides implementations of lock-free data structures. Lock-free data structures can be accessed by multiple threads without the necessity of blocking synchronization primitives such as guards. Lock-free data structures can be used in real-time systems, where blocking algorithms may lead to high worst-case execution times, to avoid priority inversion, or to increase the scalability for multi-processor machines. Lockfree provides: * boost::lockfree::fifo, a lock-free fifo queue * boost::lockfree::stack, a lock-free stack Fiber ----- :Author: Oliver Kowalke :Review Manager: Needed :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=bo…>`__ :Description: C++ Library for launching fibers (micro-threads) and synchronizing data between the fibers. Quaternions, Vectors, Matrices ------------------------------ :Author: Emil Dotchevski :Review Manager: Needed :Download: http://www.revergestudios.com/boost-qvm/ :Description: QVM defines a set of generic functions and operator overloads for working with quaternions, 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 q_traits, v_traits and m_traits templates. Stopwatches ----------- :Author: Vicente Botet :Review Manager: Anthony Williams :Download: `Boost Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=st…>`__ :Description: On top of the standard facilities of Boost.Chrono, Stopwatches provides: * Stopwatches: A facility to measure elapsed time with the ability to start, stop, suspend, or resume measurement. * Stopwatch concept * Scoped helper classes allowing to pairwise start/stop operations, suspend/resume and resume/suspend a Stopwatch. * stopwatch, model of Stopwatch capturing elapsed Clock times. * stopwatch_accumulator, model of Stopwatch capturing accumulated elapsed Clock times. * Stopclocks: a complete time reporting package that can be invoked in a single line of code. * stopwatch_reporter, convenient reporting to an output stream (including wide char streams) of the elapsed time of models of Stopwatch results. * stopclock<Clock> shortcut of stopwatch_reporter<stopwatch<Clock>> Variadic Macro Data ------------------- :Author: Edward Diener :Review Manager: Needed :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/variadic_macro_data/>`__ :Description: The variadic_macro_data library adds support and functionality for variadic macros to Boost as well as integrating variadic macros with the Boost PP library without changing the latter library in any way. Type Traits Introspection ------------------------- :Author: Edward Diener :Review Manager: Joel Falcou :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/tti/>`__ :Description: The TTI library, which is an abbreviation for the 'Type Traits Introspection' library, allows a programmer to introspect at compile time the inner elements of a C++ type. The introspection process depends on specifying the name of the inner element by different macros for different types of elements, and then using a generated metafunction to determine whether that element exists within the enclosing type. The inner elements which can be introspected are type, class template, member data, member function, static member data, and static member function. Block Pointer ------------- :Author: Phil Bouchard :Review Manager: Needed :Download: `Boost Sandbox <https://svn.boost.org/svn/boost/sandbox/block_ptr/>`__ :Description: Deterministic memory manager of constant complexity capable of handling cyclic collections. Heaps ----- :Author: Tim Blechmann :Review Manager: Andrew Sutton :Download: http://tim.klingt.org/git?p=boost_heap.git;a=snapshot;h=HEAD;sf=tgz :Description: The Heap library is an implementation of priority queues, data structures that order their elements priority. They are useful in a number of different applications especially graph search algorithms and queuing systems. Whereas the STL provides a class template std::priority_queue, Boost.Heap implements data structures with different features and performance characteristics. One key feature is the inclusion of "mutable" heaps, which allow the priorities of enqueued objects to modified and their position in the queue updated. The heaps in the library also support merging, stable sorting, and equality and less-than comparison. Assign v2 --------- :Author: Erwann Rogard :Review Manager: John Bytheway :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/assign_v2>`__ :Description: This library is an upgrade of Boost.Assign 1.0 that redefines its functionality, with optional C++0x support and new features. It expresses repetitive statements for assigning or inserting elements via a basic grammar. Network ------- :Author: Dean Michael Berris :Review Manager: Needed :Download: http://cplusplus-soup.com/2011/04/18/cpp-netlib-0-9-0-released/ :Description: This is a library that provides application layer protocol support using modern C++ techniques. It is light-weight, fast, cross-platform and is intended to be as easy to configure as possible. Algorithm --------- :Author: Marshall Clow :Review Manager: Dave Abrahams :Download: `Boost Sandbox Vault <http://www.boostpro.com/vault/index.php?action=downloadfile&filename=Boost.…>`__ :Description: Boost.Algorithm is a collection of general purpose algorithms. While Boost contains many libraries of data structures, there is no single library for general purpose algorithms. Even though the algorithms are generally useful, many tend to be thought of as "too small" for Boost. An implementation of Boyer-Moore searching, for example, might take a developer a week or so to implement, including test cases and documentation. However, scheduling a review to include that code into Boost might take several months, and run into resistance because "it is too small". Nevertheless, a library of tested, reviewed, documented algorithms can make the developer's life much easier, and that is the purpose of this library. Local ----- :Author: Lorenzo Caminiti :Review Manager: Needed :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/local/>`__ :Description: This library supports local functions, local blocks, and local exits Libraries under development =========================== See http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction for a current listing of libraries under development.

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[exception] warnings on top of trunk
by Bryce Lelbach 23 May '11

23 May '11

/opt/boost/trunk/stage/gcc-4.4.4-release/include/boost/exception/detail/exception_ptr.hpp: In function ‘void boost::rethrow_exception(const boost::exception_ptr&)’: /opt/boost/trunk/stage/gcc-4.4.4-release/include/boost/exception/detail/exception_ptr.hpp:458: warning: ‘noreturn’ function does return Is it cool for me to remove this attribute? -- Bryce Lelbach aka wash boost-spirit.com px.cct.lsu.edu github.com/lll-project

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[Review] Type Traits Extension by Frederic Bron - Review summary and decision
by Joel Falcou 23 May '11

23 May '11

Hello all, Frederic Bron's type traits extension proposal review ended up last week. In so far, we received SEVEN reviews which are all voting YES for the inclusion of Type Traits extension in Boost. So the result is that the Type Traits Extension is ACCEPTED into Boost. Suggestions include: - some clean-up in the implementation like "Renam[ing] the detail classes inside the specific namespace without using number, i.e. with a clear meaning. The use of tag, tag 2 could be renamed check_pass, check_fail or something like that." - Sensibility on cv-ref qualifiers in traits call is important. This is being addressed by Frederic. - Frederic is OK to keep the detection of void as a valid return type by using some dont_check type as default. - small comprehensive example of some of the traits like a "maybe_print function, which prints a value if the appropriate operator<< ostream overload exists, else prints "<NOT PRINTABLE>". [...] a small example like this would show a practical use of the library, and how to make use of enable_if, or some other overload method." - The main recurring suggestions found was the choice of name for the operator traits with respect to the standard naming, naming in proto and other boost libraries. This topic is still hot and alive. An alternative to the naming scheme consensus was proposed in the form of alias of commonly used operator traits. This issue is I think beyond bikeshed-color argumentation and I think it is a good point if Frederic could step up and provide a definite and rationalized answer to this point. The current status is : * the namespace options is out casue the standard didnt choose this way; * Frederic and a few other seems to favor the proto naming scheme (more or less the negate issue and the pre/post operator) * the question of a common prefix is still open * the std:: like naming seems limited as not all operators are there. Thanks to all reviewers and people participating to the discussions. Thanks to Frederic for his work.

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Small nitpick in boost::iterator
by Joel Falcou 23 May '11

23 May '11

Seems boost.Iterator pass some parameter by value in the make(Reference r) function. However, MSVC 2010 and I suspect below dont like passing value which alignment is greater than 8 ( **cough** SIMD vector **cough** ) The fix is trivial, adding const & to this function. Should I go ahead and commit this to trunk ?

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[pool] pool-based allocators and order of destruction
by John Maddock 23 May '11

23 May '11

I'm looking for second opinions on this bug report: https://svn.boost.org/trac/boost/ticket/5526#comment:1 The issue is this: if you use singleton_pool either directly or indirectly (via [fast_]pool_allocator), there is a potential order-of-destruction issue if you use it from within globally declared objects. I *think* it's OK, if the global object directly uses the singleton pool - or is it? But, things get really nasty if it's used indirectly as in the bug report via a thread_specific_ptr - the latter gets destructed very late - much later than the pool which is used by the object it points to, so the result is a program crash on exit. In general though, anything that uses indirection and "late initialization, late destruction" will cause problems. I see a number of solutions: * Document the limitation and leave it at that. * Make the singleton eternal and leak the pool's memory at program exit. * Use some kind of complex reference counting scheme so the pool is only destroyed when all it's memory has been released *and* main has exited. To be honest, I'm not thrilled by any of the above, but any opinions? Thanks in advance, John.

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Boost.Log status
by Vicente BOTET 23 May '11

23 May '11

Hi, what is going on Boost.Log? The library was accepted provisionally on March 2010 * Log - accepted provisionally March 2010; author: Andrey Semashev. Best, Vicente

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[review][autoindex] AutoIndex review ends tomorrow
by Daniel James 23 May '11

23 May '11

Hello everyone, Just a quick reminder that Saturday 21st May is the final day for the AutoIndex review. I'm going to wait for one final review before announcing the result, but other than that you need to contact me by then. thanks, Daniel James AutoIndex Review Manager

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Re: [boost] [ICL] some improvement proposals
by Joachim Faulhaber 23 May '11

23 May '11

2011/5/23 Denis <denis(a)camfex.cz>: > Hi Joachim. > I think, I explained badly and unclear the issue about contains(). > If you will have look at its implementation, you will find there a few > specialized versions of contains(), but all of them have structure of > handmadely inlined code `!below(interval, elt) && !above(interval, elt)`. So > it looks like those two functions are part of the minimal set, and > contains() made on top of them. I propose to have there the specialized > below() and above() and the general implementation of contains(). I understand. That would be a good refactoring making the code smaller and more concise. Good proposal :) Cheers, Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

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Fwd: [Boost-users] condensed overview of boost
by Joachim Faulhaber 23 May '11

23 May '11

---------- Forwarded message ---------- From: Joachim Faulhaber <afojgo(a)googlemail.com> Date: 2011/5/23 Subject: Re: [boost][Boost-users] condensed overview of boost To: boost(a)lists.org, boost-users(a)lists.boost.org Hi Olaf, Hallo Dresden, 2011/5/12 Olaf Krzikalla <olaf.krzikalla(a)tu-dresden.de>: > Hi @boost, > > recently I've given some lectures about some selected boost libraries. Thank you for teaching boost! (boo to the community for not answering for so long ;) > After > that the audience expressed the wish to get an overview over all current > boost libraries. Thus for my next lecture I sat down and digged through the > complete 1.46 for several day. I found a lot of useful stuff, but I also > found a lot of obsolete, superseded, replaced or will-be-superseded stuff. > Some libraries seems to be sub-libs of other libs. Is there an overview of > inner lib relations and the actual lib state wrt. to the overall > development? There is an overview on the boost web-site www.boost.org of course in an synoptic quality with short descriptions of each library. As far as I know there is no single documentation on inter library relationships that is maintained, correct me if I'm wrong. Generated dependency graphs were provided by Chrisoph Heindl in December 2008. http://lists.boost.org/Archives/boost/2008/12/146290.php http://picasaweb.google.com/christoph.heindl/BoostDependencies1370 for boost-1.37 but not updated later. > The issues I've found so far: > > - Compatibility: very narrow. Is it still needed as a public lib? > - Functional, MemFun: superseded by Bind > - Call Traits, Functional/Forward, Lambda: will be superseded by C++0x > - Interval: can this become a sub-lib of ICL? boost::numeric::interval is closed interval on numeric types with a focus on interval arithmetic. It is also suitable handle numeric precision problems AFAIK, but I'm not an expert for that. In contrast ICL has a focus on the set character of intervals and their composition in interval containers. Non numeric intervals are possible as long as there is an ordering on the domain_type. I think it is unfortunate that ICL and numeric::interval do not interplay well. One of the main obstacle are the fixed closed borders of numeric::intervals, that lead to problems when adding or subtracting intervals to and from interval containers. There were discussions on this on the list but the authors of numeric::interval seemed not to be active at the time. Since numeric::intervals serve numeric purposes and icl::interval serve more general pusposes I think they can coexist happiely. As long a numeric::interval is not actively maintained, I don't think there is a chanche for change. > - Meta State Machine / Statechart: whats the actual difference? I.e. Meta State Machine is a library that generates finite state machines completely at compile-time from meta code. MSN is more expensive at compile time but may generate even faster code than a "traditional" FSM. Maybe Christophe can comment on this. > which problem is solved by one lib but not by the other? > - Fusion & Tuple: how are these related? Could boost::tuple become a > typedef to boost::fusion::vector. > > I know that most of these relations are there for historical reasons and > won't be changed. However I wish it had been documented somewhere. That > would make an in-depth introduction of boost a lot easier. There is no ready made structure or institution within boost for this. But definitely there are people who have similar thoughts, concerns and intentions. It depends if someone is going to contribute and/or is taking the lead for an effort like this. As mentioned above Chrisoph Heindl provided generated dependency graphs. Boris Schäling wrote an online book http://www.highscore.de/cpp/boost/index.html that has been translated by others. Paul Bristow cares on documentation quality for the math stuff. Robert Ramey, Dean Berris and others had initiatives about redesigning the boost web-site, just to mention a few things. So your effort on creating an overview and document on inter library relationships could be an own contribution and other could join in. Thanks again, Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

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[ICL] interval_map::find(const domain_type_comparable&) instead of interval_map::find(const domain_type&)
by Denis 23 May '11

23 May '11

Hi Joachim One small note about Icl maps. I think would be useful to make interval_map::find()'s function accept any type comparable to map's key. For example, the key type is std::string and the user want to search using a 0-terminated string or a string defined as arbitrary pointer and a length. Then the user will have to allocate the temporary string only to pass it to interval_map::find() You may argue that the std::map works same way. But there is the difference. If I want to do the trick above, I can use boost::multi_index or at least instead of std::map<std::string, ValueT> I can define something like std::map<tuple<const char*, size_t>, tuple<std::string, ValueT>> with key's const char* and size_t pointing to the data hosted in value. This is not possible with interval_map, where the values can be joined

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