February 2010 - Boost-users

Help with shared_ptr and template
by Mario Chacon 10 Sep '10

10 Sep '10

Hello: I have this problem and I do not how to fix it, I know I cannot write template typedefs, its a limitiation of the C++ syntax, right? or I'm wrong? I saw that the best way is to wrap your typedefs in a struct, which can be templated, but I'm still stack with problems. The best way to explain it's with an example: #include <cstdlib> #include <iostream> #include <boost/shared_ptr.hpp> template< typename tvalue > class CValue { public: CValue( tvalue value ) : value_(value) {}; private: tvalue value_; }; template< typename tvalue > struct Type{ typedef boost::shared_ptr< CValue< tvalue > > pValue; }; int main(int argc, char *argv[]) { Type<bool>::pValue a; return EXIT_SUCCESS; } How can I create a shared_ptr for the template class "CVALUE"?? Please I do not know what else I can prove... :( Thank you.. Mario.. Salu2...

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[array] range check (at compile time)
by alfC 23 Jun '10

23 Jun '10

Hi, Lately I find myself using boost::array intesively, specially in small demo programs. Sometimes, when "manually" accessing the elements I type a index out of range. The library can detect these errors once the program is running but I found this a waste, also I was surprised not to see this kind of static check not implemented in the library. So I wanted to see if I could enforce range checking at compile time, and I come out with this solution. namespace boost{ //sorry about the namespace name template<size_t IDX, typename T, size_t N> const T& get(boost::array<T, N> const& arr){ BOOST_STATIC_ASSERT(IDX<N); return arr[IDX]; } template<size_t IDX, typename T, size_t N> T& get(boost::array<T, N>& arr){ BOOST_STATIC_ASSERT(IDX<N); return arr[IDX]; } } #include<iostream> void main(){ boost::array<double, 3> a = {1,2,3}; std::clog<<boost::get<2>(a)<<std::endl; // ok, (namespace specification needed, why?) std::clog<<boost::get<5>(a)<<std::endl; //does not compile return 0; } (I though about using enable_if instead of BOOST_STATIC_ASSERT but that would be too much overengineering.) Is this implemented already in some other way? Alfredo

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[date_time] howto determine date format?
by Markus Werle 16 Apr '10

16 Apr '10

Hi! With the code below I try to automagically determine the date format found in input files. I'd expect the code below to find the date format "%d.%m.%Y" for "05.02.2008", but I got surprised by obtaining "%m/%d/%Y". A major pain it is with those dates. Whether my shallow knowledge of locales and imbue or boost::date_time (from boost-1.37.0) is to be blamed is beyond my horizon. I feel like date accepts '.' where I said "expect '/'", so I think this should be changed. I may be wrong. Could you please shed some light on the issue? Thanks, Markus #include <boost/assign/list_of.hpp> #include <boost/date_time/posix_time/posix_time.hpp> #include <boost/date_time/gregorian/gregorian.hpp> #include <boost/date_time/local_time/local_time.hpp> #include <boost/foreach.hpp> #include <boost/algorithm/string.hpp> #include <string> #include <list> inline std::string determine_date_format(std::string const & s) { using namespace boost::assign; using namespace boost::gregorian; std::list<std::string> possible_formats = // TODO: add others here! list_of ("%Y-%m-%d")("%Y/%m/%d")("%m/%d/%Y")("%d.%m.%Y"); bool inform_user = false; BOOST_FOREACH(std::string const & format, possible_formats) { if (inform_user) { std::cout << "Trying format '" << format << "' ..." << std::endl; } try { date_input_facet * input_facet = new date_input_facet(format.c_str()); std::istringstream iss(s); iss.imbue(std::locale(iss.getloc(), input_facet)); date d(not_a_date_time); iss >> d; if (!iss.fail() && (!d.is_not_a_date())) { return format; } std::cout << "WARNING: date format '" << format << "' does not match '" << s << "'." << std::endl; inform_user = true; } catch(...) { } } std::cout << "WARNING: date format not recognized. " << "Please reconfigure your measurement equipment " << "to ISO standard output!" << std::endl; return ""; } int main() { std::string the_date = "05.02.2008"; std::string format = determine_date_format(the_date); std::cout << the_date << " has date-time-format " << format << std::endl; return 0; }

2 1

Boost static linking
by Alex Farber 24 Mar '10

24 Mar '10

I am using the Boost library with g++ on Linux. When I built this library, I executed this command: ./bjam (without parameters). My lib directory looks like this: libboost_thread.a libboost_thread.so libboost_thread.so.1.41.0 ... Building the project using Thread library, I added boost_thread to the linker dependencies list. Now my program depends on the shared library libboost_thread.so.1.41.0. For my purposes, I need to make static linking, to exclude runtime dependency. How can I do this? -- View this message in context: http://old.nabble.com/Boost-static-linking-tp27714367p27714367.html Sent from the Boost - Users mailing list archive at Nabble.com.

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Multithread event handling
by Alessandro Bellina 21 Mar '10

21 Mar '10

Hello boost, Traditionally, I think of services as having a thread pool or manually managed threads to handle requests and produce responses. I have been looking at boost::asio and tbb as an alternative to this in order to take advantage of multiple cores. Also, I think that implementing an event handler with asio or tbb should provide better performance over a threadpool. Do you have any suggestions? So far, I have implemented an example using tbb::task_group and spawned tasks. This yielded full CPU utilization, but since these are very short lived tasks, the task creation overhead took over. Using io_service, it seems to be as easy as posting to the service, and running it among different threads. Would this be the correct approach for my case? Can somebody share their experiences on libraries or patterns used to implement an event handling mechanism? Thanks, Alessandro

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Link issue with condition_variable
by Bradley W. Settlemyer 19 Mar '10

19 Mar '10

Hello, I'm using boost for the first time and I'm struggling to link my program. I've added libboost_pthread-mt to the link link (which got most of the symbols), but I still can't seem to get the symbols for the condition variables. The issue could be with the code, as I find the lock-mutex-condition_variable interactions to be very confusing, but it does appear to be a link issue. Consider the following error message emitted during link command: mpicxx <objects> -D_FILE_OFFSET_BITS=64 -L/lib64 -lfuse -lrt -ldl -lboost_thread-mt -lpthread -o aio_benchmark src/aio/thread_pool_adaptive_writer.o: In function `aio::ThreadPoolWriter::Write(aio::File*, std::vector<int, std::allocator<int> >, void*, unsigned long)': /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:59: undefined reference to `boost::condition_variable::notify_all()' /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:63: undefined reference to `boost::condition_variable::wait(boost::unique_lock<boost::mutex>&)' src/aio/thread_pool_writer.o: In function `aio::ThreadPoolWriter::threadWait()': /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:76: undefined reference to `boost::condition_variable::wait(boost::unique_lock<boost::mutex>&)' /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:110: undefined reference to `boost::condition_variable::notify_one()' Is condition variable in a different library? I am using the boost stuff distributed with Fedora 11: boost-1.37.0-7.fc11.x86_64 boost-devel-1.37.0-7.fc11.x86_64 Cheers, Brad

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[boost] [chrono] v0.4 New thread_clock
by vicente.botet 14 Mar '10

14 Mar '10

Hi, I'm pleased to announce the version 0.4 of the Boost.Chrono library. The implementaton is stable, I don't plan to add more features before review. I'll concentrate in improving the documentation and the tests. I know that review managers are hard to find, so if you are interested in the library, please contact me or the Review Wizards. The library can be downloaded from http://www.boostpro.com/vault/index.php?action=downloadfile&filename=chrono… and the documentation is online on the sandbox http://svn.boost.org/svn/boost/sandbox/chrono/libs/chrono/doc/html/index.ht…. New Features since v0.3.2: * Suspendible Clock concept + template class suspendible_clock<> * Added scope_suspend which do suspend/resume if the Clock is a model of Suspendible Clock concept, and nothing otherwise. * thread_clock support on platforms providing it natively. * Added support for wide character for stopwatch_reporter, stopclock, and stopclock_accumulator. * digital_time renamed t24_hours Perf * Added performances measures. Bug Fixes * Bug on timeval_demo. time_point t(duration(xtime(0))); // this was taken as a function declaration gettimeofday((timeval*)&t, 0); return t; time_point t(duration(xtime(0))); // this was taken as a function declaration gettimeofday((timeval*)&t, 0); return t; by timeval tv; gettimeofday(&tv, 0); xtime xt( tv.tv_sec, tv.tv_usec); return time_point(duration(xt)); * Bug on run_timer_test (add a global variable to avoid optimization that removes completely the code to be measured Best regards, _____________________ Vicente Juan Botet Escribá

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[Gil new_io] Some questions and remarks
by Olivier Tournaire 10 Mar '10

10 Mar '10

Hi all, I have just checkout gil-contributions svn repo ( http://code.google.com/p/gil-contributions/) in order to test new_io in which I am really interested. Thank you for this very usefull job! I have however some remarks and questions about some compilation issues. 0) The code seems to have been written and tested on Windows. Am I right (see my remarks thereafter)? For ex., why do you use "\\" in paths (paths.hpp) and not "/"? 1) Which Boost version is required? I first tried with 1.40, but it did not work because of missing accessors in boost::gil::variant (index() and bits()). Did they appear in 1.41 or 1.42? With 1.42, this issue is solved. 2) While compiling tests, I ran into some issues. I am running the code on an Ubuntu 9.10, with g++-4.3.4. I was able to fix some of them, but others are still problematic: 2.1) For each test, I have to add at the beginning the 2 following lines: #define BOOST_TEST_DYN_LINK #define BOOST_TEST_MODULE my application tests It probably comes from my little knowledge of boost unit_test_framework. Could you explain? 2.2) For each test, the compiler gave the following error: /usr/local/include/boost/gil/extension/io_new/detail/dynamic_io_new.hpp:75: error: there are no arguments to ‘io_error’ that depend on a template parameter, so a declaration of ‘io_error’ must be available I simply add in *[...]/detail/dynamic_io_new.hpp* an unclude directive at the beginning of the file : #include <boost/gil/extension/io/io_error.hpp>. Still do not understand how it can work wihtout this ... 2.3) I had a similar error with *[...]/formats/bmp/read.hpp*: /usr/local/include/boost/gil/extension/io_new/formats/bmp/read.hpp:833: error: there are no arguments to ‘get_info’ that depend on a template parameter, so a declaration of ‘get_info’ must be available I simply changed line 833 from get_info() to parent_t::get_info(). Now works. 2.4) Some typename are missing (still do not know how visual can infer types ...): - [...]/formats/jpeg/read.hpp, line 336: *typename*Image::view_t - [...]/formats/bmp/is_allowed.hpp, line 73: *typename*View::value_type - [...]/formats/pnm/read.hpp, line 419: *typename* Image::view_t Everything works with these changes. 2.5) png_read_test failed. Obviously, this is a portability issue. PNG filenames for testing are uppercase, while they are lowercase in the test code. I think that is also missing in the code the path to png files. For example, in basic_format_test, instead of test_file< gray1_image_t >( "basn0g01.png" ); it soulhd be: test_file< gray1_image_t >(* png_in + "BASN0G01.PNG"* ); I did not rename all files, so I am unable to try the test. 2.6) Some tests fail to compile or link. Here are the errors: - *all_formats_test.cpp*: In file included from /usr/include/png.h:481, from /usr/local/include/boost/gil/extension/io_new/png_tags.hpp:23, from /usr/local/include/boost/gil/extension/io_new/png_read.hpp:22, from /usr/local/include/boost/gil/extension/io_new/png_all.hpp:22, from /home/olivier/work/dev/lib/gil-contributions-read-only/gil_2/libs/gil/io_new/test/all_formats_test.cpp:7: /usr/include/pngconf.h:335: error: expected constructor, destructor, or type conversion before ‘.’ token /usr/include/pngconf.h:336: error: ‘__dont__’ does not name a type - *pnm_reads_test.cpp*: pnm_read_test.cpp.o: In function `pnm_test::read_header_test::test_method()': pnm_read_test.cpp:(.text+0x24c0): undefined reference to `boost::gil::pnm_image_type::_color_asc' collect2: ld returned 1 exit status Do not really understand since _color_asc is a typedef defined in pnm_tags.hpp ... - *jpeg_old_test.cpp* (sorry for the message ...): /usr/local/include/boost/gil/extension/io_new/formats/jpeg/write.hpp: In function ‘typename BinaryOp::result_type boost::gil::detail::apply_operation(const boost::gil::variant<Types>&, const Info&, BinaryOp) [with Types1 = boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0>, Info = boost::gil::image_write_info<boost::gil::jpeg_tag, boost::gil::detail::no_log>, BinaryOp = boost::gil::detail::dynamic_io_fnobj<boost::gil::detail::jpeg_write_is_supported, boost::gil::detail::writer<boost::gil::detail::file_stream_device<boost::gil::jpeg_tag>, boost::gil::jpeg_tag, boost::gil::detail::no_log> >]’: /usr/local/include/boost/gil/extension/io_new/formats/jpeg/write.hpp:283: instantiated from ‘void boost::gil::detail::dynamic_image_writer<Device, boost::gil::jpeg_tag, boost::gil::detail::no_log>::apply(const boost::gil::any_image_view<Views>&, const boost::gil::image_write_info<boost::gil::jpeg_tag, boost::gil::detail::no_log>&) [with Views = boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0>, Device = boost::gil::detail::file_stream_device<boost::gil::jpeg_tag>]’ /usr/local/include/boost/gil/extension/io_new/detail/write_view.hpp:302: instantiated from ‘void boost::gil::write_view(Device&, const boost::gil::any_image_view<Types2>&, const boost::gil::image_write_info<FormatTag, Log>&, typename boost::enable_if<typename boost::mpl::and_<typename boost::gil::detail::is_output_device<IODevice>::type, typename boost::gil::is_format_tag<FormatTag>::type, mpl_::bool_<true>, mpl_::bool_<true>, mpl_::bool_<true> >::type, void>::type*) [with Device = boost::gil::detail::file_stream_device<boost::gil::jpeg_tag>, Views = boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0>, FormatTag = boost::gil::jpeg_tag, Log = boost::gil::detail::no_log]’ /usr/local/include/boost/gil/extension/io_new/detail/write_view.hpp:357: instantiated from ‘void boost::gil::write_view(const String&, const boost::gil::any_image_view<Types2>&, const boost::gil::image_write_info<FormatTag, Log>&, typename boost::enable_if<typename boost::mpl::and_<typename boost::gil::detail::is_supported_path_spec<P>::type, typename boost::gil::is_format_tag<FormatTag>::type, mpl_::bool_<true>, mpl_::bool_<true>, mpl_::bool_<true> >::type, void>::type*) [with String = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, Views = boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0>, FormatTag = boost::gil::jpeg_tag, Log = boost::gil::detail::no_log]’ /usr/local/include/boost/gil/extension/io_new/jpeg_io_old.hpp:169: instantiated from ‘void boost::gil::jpeg_write_view(const String&, const View&, int) [with String = std::basic_string<char, std::char_traits<char>, std::allocator<char> >, View = boost::gil::any_image_view<boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0> >]’ /home/olivier/work/dev/lib/gil-contributions-read-only/gil_2/libs/gil/io_new/test/jpeg_old_test.cpp:98: instantiated from here /usr/local/include/boost/gil/extension/io_new/formats/jpeg/write.hpp:243: error: invalid initialization of non-const reference of type ‘boost::gil::variant<boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0> >::base_t&’ from a temporary of type ‘boost::gil::variant<boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0> >::base_t’ /usr/local/include/boost/gil/extension/io_new/formats/jpeg/write.hpp:213: error: in passing argument 1 of ‘typename Op::result_type boost::gil::detail::apply_operation_base(Bits&, size_t, const Info&, Op) [with Types = boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0>, Info = boost::gil::image_write_info<boost::gil::jpeg_tag, boost::gil::detail::no_log>, Bits = boost::gil::variant<boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgba8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::rgb8_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray16_pixel_t*> > >, boost::mpl::v_item<boost::gil::image_view<boost::gil::memory_based_2d_locator<boost::gil::memory_based_step_iterator<boost::gil::gray8_pixel_t*> > >, boost::mpl::vector0<mpl_::na>, 0>, 0>, 0>, 0> >::base_t, Op = boost::gil::detail::dynamic_io_fnobj<boost::gil::detail::jpeg_write_is_supported, boost::gil::detail::writer<boost::gil::detail::file_stream_device<boost::gil::jpeg_tag>, boost::gil::jpeg_tag, boost::gil::detail::no_log> >]’ /usr/local/include/boost/gil/extension/io_new/formats/jpeg/write.hpp:243: error: return-statement with a value, in function returning 'void' Apart png_read_test and its case sensitive problem, all compiled and linked tests run successfully. This is a really good new! However, could you please help regarding the issues above? Please note that if you are intersted in a Linux developper/tester for gil, I am wiling to do some jobs ... Best regards, Olivier

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[Review] ITL review starts today, February 18th
by Hartmut Kaiser 08 Mar '10

08 Mar '10

Hi all, The formal review of the Interval Template Library (ITL) starts today, February 18th, 2010 and will end February 27th, 2010. ITL is being developed by Joachim Faulhaber. ------------------------------------------------ About the library: The Interval Template Library (ITL) is a library of interval containers that facilitates computations on collections of intervals and associated values. Use cases of such computations typically occur in the date and time problem domain, when collections of time intervals with associated data are analyzed, combined and aggregated. But the scope of applications for interval containers is more general and not limited to date and time problems. Interval containers allow to access and manipulate collections of intervals on an abstract level as sets and maps (of elements), but also to exploit segmental information that is given by the interval borders. Interval containers are fairly generic. They can be instantiated with discrete domain (or key) types like integral numeric types or boost::date or time types. But they also work with continuous domain types like double, rational or string. Using the latter allows to represent infinite sets and maps. The interface of the interval containers strives to be very intuitive and in line with the stl and other boost libraries. * The set theoretic operations union, difference, intersection and symmetric difference are available as operators for all interval containers and for many useful overloads between them. * There is iterator support on the level of segments and interval containers can be combined with stl containers of intervals via stl algorithms. * For discrete domain types, element iterators are available which makes interval sets and maps models of SortedAssociative Containers so they can be used with many stl algorithms. All interval containers are addable and subtractable. The addability and subtractability concept of the ITL leads to a general mechanism of aggregation on interval_maps which is called 'aggregate on overlap'. Exploiting 'aggregate on overlap' allows to compute many useful aggregation results in a simple and abstract manner. The ITL's Set and Map concepts are defined by a signature and collections of laws or axioms. Those semantical constraints have been validated using automatic law based tests. This gives the library both a well founded formal specification and an unusual thorough test base. The ITL emerged out of real world use cases and is successfully used at Cortex Software GmbH since a couple of years in the production code of various applications. On the boost developer's list it has been proposed in four previews and a review request since May 2008 and has been refactored and refined according to boost standards and suggestions from the list. The ITL is available from the boost vault: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=itl_3_2 _0.zip&directory=Containers Documentation is online available at: http://www.herold-faulhaber.de/boost_itl/doc/libs/itl/doc/html/index.html The current sources are in the sandbox: https://svn.boost.org/svn/boost/sandbox/itl/ ------------------------------------------------ Everybody on this list is invited to participate in this formal review. I hope to see your review of this library, including your vote, and I welcome your participation in the discussions on the Boost mailing list. Please always state in your review, whether you think the library should be accepted as a Boost library. Additionally, please consider giving feedback on the following general topics: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? Regards Hartmut Review Manager --------------- Meet me at BoostCon www.boostcon.com

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[serialization] class versioning changes in boost 1.42
by David Raulo 02 Mar '10

02 Mar '10

Hi, It seems that the serialization library shipped with boost 1.42 changed the way class versions are handled. The version_type which used to be an unsigned int is now an uint_least16_t, although I found no mention of that in the release notes. The problem is that we are using a date-based versioning scheme for our classes (for example a developer making a change in some class on 2010-02-22 would increment the class version to 20100222). This scheme worked great for a couple of years, and helped us fix our backward compatibility bugs after the fact. Unfortunately, these big version numbers do not fit in 16-bit integers. As a consequence, the version string output in xml archives with the latest boost-serialization for this example would be 46206 instead of 20100222, breaking our reloading code. May I ask why this change was made? Would it be possible to revert it for the next boost release? If not, anyone has suggestions how we could fix our code while maintaining backward compatibility ? (we have old archives in the wild generated with various releases of our code, which we need to be able to reload). Thanks for any help, David.

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