- Boost - lists.preview.boost.org

[any][quickbook] Recent compile failure gcc vs. clang..
by Rene Rivera 13 May '13

13 May '13

Not sure when this started failing other than it was some time this past week.. ===== Froggy:quickbook grafik$ pwd /Users/grafik/devroots/Boost/trunk/tools/quickbook Froggy:quickbook grafik$ b2 toolset=clang ...patience... ...patience... ...found 1735 targets... Froggy:quickbook grafik$ b2 toolset=darwin ...patience... ...patience... ...found 1735 targets... ...updating 3 targets... darwin.compile.c++ ../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static/quickbook.o ../../boost/any.hpp: In function ‘ValueType boost::any_cast(boost::any&) [with ValueType = const int&]’: ../../boost/any.hpp:308: instantiated from ‘ValueType boost::any_cast(const boost::any&) [with ValueType = const int&]’ ../../boost/program_options/variables_map.hpp:69: instantiated from ‘const T& boost::program_options::variable_value::as() const [with T = int]’ src/quickbook.cpp:387: instantiated from here ../../boost/any.hpp:292: error: forming reference to reference type ‘const int&’ ../../boost/any.hpp:294: error: forming reference to reference type ‘const int&’ ../../boost/any.hpp: In function ‘ValueType boost::any_cast(boost::any&) [with ValueType = const std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&]’: ../../boost/any.hpp:308: instantiated from ‘ValueType boost::any_cast(const boost::any&) [with ValueType = const std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&]’ ../../boost/program_options/variables_map.hpp:69: instantiated from ‘const T& boost::program_options::variable_value::as() const [with T = std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]’ src/quickbook.cpp:421: instantiated from here ../../boost/any.hpp:292: error: forming reference to reference type ‘const std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&’ ../../boost/any.hpp:294: error: forming reference to reference type ‘const std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&’ ../../boost/any.hpp: In function ‘ValueType boost::any_cast(boost::any&) [with ValueType = const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&]’: ../../boost/any.hpp:308: instantiated from ‘ValueType boost::any_cast(const boost::any&) [with ValueType = const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&]’ ../../boost/program_options/variables_map.hpp:69: instantiated from ‘const T& boost::program_options::variable_value::as() const [with T = std::basic_string<char, std::char_traits<char>, std::allocator<char> >]’ src/quickbook.cpp:438: instantiated from here ../../boost/any.hpp:292: error: forming reference to reference type ‘const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&’ ../../boost/any.hpp:294: error: forming reference to reference type ‘const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&’ ../../boost/system/error_code.hpp: At global scope: ../../boost/system/error_code.hpp:222: warning: ‘boost::system::posix_category’ defined but not used ../../boost/system/error_code.hpp:223: warning: ‘boost::system::errno_ecat’ defined but not used ../../boost/system/error_code.hpp:224: warning: ‘boost::system::native_ecat’ defined but not used "g++" -ftemplate-depth-300 -O3 -finline-functions -Wno-inline -Wall -gdwarf-2 -fexceptions -g0 -DBOOST_ALL_NO_LIB=1 -DBOOST_DETAIL_CONTAINER_FWD -DBOOST_FILESYSTEM_NO_DEPRECATED -DBOOST_FILESYSTEM_STATIC_LINK=1 -DBOOST_SYSTEM_STATIC_LINK=1 -DNDEBUG -I"../.." -c -o "../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static/quickbook.o" "src/quickbook.cpp" ...failed darwin.compile.c++ ../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static/quickbook.o... ...skipped <p../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static>quickbook for lack of <p../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static>quickbook.o... ...skipped <p../../dist/bin>quickbook for lack of <p../../bin.v2/tools/quickbook/src/darwin-4.2.1/release/link-static>quickbook... ...failed updating 1 target... ...skipped 2 targets... ===== Seems some of the std::any conformance changes broke for the GCC included in the Xcode 4.6.2. -- -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim - grafikrobot/yahoo

4 6

Re: [boost] [config] BOOST_FORCEINLINE for clang
by Daryle Walker 13 May '13

13 May '13

I didn’t know that the GCC emulation went that deep. Anyway, I think that Clang should eventually wean away from being a GCC copycat, and that comment would be necessary. And if that doesn’t happen, another maintainer may wonder about Clang support, not knowing the details on Clang’s GCC emulation, and seeing the comment will save a trip to this mailing list. Sent from Windows Mail From: Mathias Gaunard Sent: ‎Monday‎, ‎May‎ ‎13‎, ‎2013 ‎5‎:‎45‎ ‎AM On 13/05/13 07:12, Daryle Walker wrote: > You should include a comment in the GCC section that it also works for Clang, > due to Clang's GCC emulation. That way, later maintainers won't be wondering > if Clang support should be added. (And help debugging if Clang ever stops > emulating GCC by default.) Isn't it common knowledge that Clang is compatible with GCC and pretends to be GCC 4.2, and that therefore most GCC-specific code will just work with Clang out of the box?

1 0

boost modularization questions
by Eric Cornelius 13 May '13

13 May '13

Hi all, Out of curiosity, is the plan to move to a git pull-request model once the modularization process is complete? Or is github being used simply as a convenient mirror and interface for browsing code and history? Also, I have some changes to the Jamroot and boostcpp.jam files for improving modularization builds, which aggregate all the public headers from modules into the standard boost/... layout within the install/include directory, as well as implicitly setting up include paths during the initial build process. https://github.com/EricMCornelius/boost/commit/cdc08a1afa4b3df85997d54d9e6a… Cheers, Eric Cornelius

3 2

Boost range - Add variadic join/zip
by Gonzalo BG 12 May '13

12 May '13

Code available here: https://gist.github.com/gnzlbg/5547905 Let, std::array<double,4> a = {{ 1, 2, 3, 4 }}; std::list<int> b = { 11, 22, 33, 44 }; std::deque<int> c = { 111, 222, 333, 444 }; std::vector<int> d = {1111,2222,3333,4444 }; If the values stored in a container have the same type, I would like to iterate over different containers as if it were a single one, and: /// - modify its value for(auto&& i : join(b,c,d)) { i += 1; } /// - use it with boost algorithms boost::transform(join(b,c,d),begin(join(b,c,d)),[&](int j){ return j * 2; }); /// - and read it for(const auto& i : join(b,c,d)) { std::cout << i << "\n"; } Another problem I usually face is manipulating data that has different types. This data is usually stored in different containers for efficiency, but it does belong together. Zip can be used to iterate throw a row of this kind of table-like data structure: for(const auto& t : zip(a,b,c,d)) { std::cout << t << "\n"; } However, boost's zip_iterators are not writable. I don't really think it would be possible to make them writable, but that would allow code like this: typedef decltype(*begin(zip(a,c,d))) tIt; boost::sort(zip(a, c, d), [](const tIt& i, const tIt& j){ return boost::get<0>(i) > boost::get<0>(j); }); which sorts the three containers in lock-step after the values in the first container (a). Some parts of this code can be implemented with minor extensions to boost range. A variadic join might look like this: template<class C> auto join(C&& c) -> decltype(boost::make_iterator_range(c)) { return boost::make_iterator_range(c); } template<class C, class D, class... Args> auto join(C&& c, D&& d, Args&&... args) -> decltype(boost::join(boost::join(boost::make_iterator_range(std::forward<C>(c)), boost::make_iterator_range(std::forward<D>(d))), join(std::forward<Args>(args)...))) { return boost::join(boost::join(boost::make_iterator_range(std::forward<C>(c)), boost::make_iterator_range(std::forward<D>(d))), join(std::forward<Args>(args)...)); } A variadic zip is more complicated. If we want write access we cannot use boost zip_iterator. Still one can use Anthony Williams' TupleIterator: template <class... T> auto zip(T&&... c) -> boost::iterator_range< decltype(iterators::makeTupleIterator(std::begin(std::forward<T>(c))...))> { return boost::make_iterator_range (iterators::makeTupleIterator(std::begin(std::forward<T>(c))...), iterators::makeTupleIterator(std::end(std::forward<T>(c))...)); } For read-only access one could use boost::zip_iterator, but I think write-access is _really_ important (e.g. sort wouldn't work). Would it be possible to add similar functionality to boost range? This code wouldn't work without the help of everyone who participated in the following SO discussions: - http://stackoverflow.com/questions/14366576/boostrangejoin-for-multiple-ran… - http://stackoverflow.com/questions/13840998/sorting-zipped-locked-container… and without Anthony Williams's tupleIterator. See also http://www.justsoftwaresolutions.co.uk/articles/pair_iterators.pdf Bests, Gonzalo BG

5 9

[chrono/date] conversion between concrete dates
by Vicente J. Botet Escriba 12 May '13

12 May '13

Hi, as the conversion between concrete dates could be expensive I guess that these conversion must be explicit. But this has some consequences when used the implicit conversion was hidden a not efficient implementation, e.g. date ISO_week_start = mon <= jan/day(4)/y; jan/day(4)/y should be ymd_date as is the efficient representation. The date generator was declared as date operator<=(weekday wd, date x); but it works efficiently only for days_date. If we provide only the functions that are efficient we should declare it as days_date operator<=(weekday wd, days_date x); So the preceding expression would need an explicit conversion days_date ISO_week_start = mon <= days_date(jan/day(4)/y); Do we want to go on this direction? A radical alternative to the explicit construction, if we want to make evident that the conversion operation could be expensive, is to use a compute_ factory days_date ISO_week_start = mon <= compute_days_date(jan/day(4)/y); Best, Vicente P.S. the generator function is just an example needing explicit conversion.

4 18

[spirit] [lex] semantic actions to handle and manipulate eoi
by Andreas Pokorny 12 May '13

12 May '13

Hi, I want to replace a flex lexer with boost.spirit.lex. We implemented an include-like functionality inside the lexer semantic actions: include { BEGIN(incl) } <EOF> { leaveCurrentFile(); popScannerState(); } <incl> { ".+" { openNewFile(); pushScannerState(); BEGIN(INITIAL); } } Is there a way to do that in lexertl? I thought about extending the spirit file_iterator but found that unwieldy. So I now consider adding a semantic actions that are allowed to change lex::_eoi and the ability to have a eoi token or just a semantic action to handle eoi. Is that a reasonable way of implementing that? regards Andreas

1 0

[1.54.0][release] Provisional schedule
by Daniel James 12 May '13

12 May '13

Hello everyone, I've put up a provisional schedule for the next release on the calendar. You can see it at: http://www.boost.org/development/ It targets a 1st July release date, and follows the usual schedule relative to that date. The deadlines for the release branch are pretty soon, particularly the deadline for new libraries which is just a week away. Also, the deadline for new features is just after C++Now. If any of this is a problem let us know now. The release after that will probably target November 1st (as normal), which will give a 4 month release cycle. If the git modularization is considered ready, this will allow a little extra time to deal with any disruption caused (possibly not enough...). How does that sound? Any thoughts? Daniel

9 34

[GSOC] XML library of Boost
by Amos Ji 12 May '13

12 May '13

Hi All, I'm a graduate student from Fudan University in China. And I hope to contribute some code to Boost during the GSOC. I've scanned the idea page. The ideas in the page are all very interesting and challenging. But what I'm interested in most is XML library, which is at the bottom of page. I think the XML format is the most popular standard for storing information so it's important for Boost to have a good XML library. However, I know Boost contains RapidXML in property_tree library to parse XML file. So what I want to make sure is I need to implement a new XML parser in this project instead of make enhancement for RapidXML. Am I correct? If so, I have some ideas to share with you. In my opinion, an XML parser must be able to do these things: 1. To Iterate over DOM nodes tree; 2. To access the values of nodes and their attributes quickly; 3. To insert or delete nodes or attribute of an exact node easily; 4. To generate new XML from the structure which stores XML in the library. And there are some optional function too: 1. To support XPATH; 2. To validate whether the XML file is valid; 3. To support various encoding; 4. To manage memory better; 5. To support regular expression. The ideas are not mature now. I'll improve them in my proposal. In fact, it's not easy to implement a perfect XML parser but I'll do my best. And I have another question. Who will mentor this XML library project? Thanks for your patience to read this email. Sincerely, Mingchao -- Amos Ji(Mingchao Ji) Master in School of Information Science and Engineering, Fudan University MSN: jmc891205(a)hotmail.com E-mail: jmc891205(a)gmail.com

14 36

[type_erasure] How to have just one behavior from relaxed without inheriting the other behaviors
by Felipe Magno de Almeida 12 May '13

12 May '13

Hello, I need to create a type_erasure::any with just this behavior from relaxed: copy assignment of any uses the copy constructor if it can't use assignable(either because assignable is missing, or because the stored types do not match). But without adding the other behaviors, is there a way to implement this? Regards, -- Felipe Magno de Almeida

2 1

[math][constants] mathematical constants page deserves to be more visible in the documentation
by Andrew Hundt 11 May '13

11 May '13

I believe the Boost.math toolkit mathematical constants are an extremely useful feature, yet it is extremely difficult to find. Every time I try to browse to it I try searching boost.org/libs, then try the math library page and cannot find the links at either of those locations. In fact, I'm not exactly sure how to browse to it and instead use saved bookmarks. I it would be worthwhile if there was some direct link or mention of it on boost.org/libs/math at minimum, and possibly even directly on boost.org/libs . Here is the mathematical constants page I am referring to: http://www.boost.org/doc/libs/release/libs/math/doc/sf_and_dist/html/math_t… Any thoughts on this idea? Cheers! Andrew Hundt

5 7