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Permission to merge to master during release
by Glen Fernandes 26 Jul '14

26 Jul '14

The small change: https://github.com/boostorg/smart_ptr/commit/88f0a98d71 Renaming identifier of a member function from "free" to anything that is not "free" to compensate for _CRTDBG_MAP_ALLOC users in MSVC. (A colleague at Microsoft reported this to me today; he tried the 1.56.0 beta with MSVC and with _CRTDBG_MAP_ALLOC defined. It doesn't like a member function named "free"). Glen

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Help about boost library x64 used in the LibLas tools
by Luca Nardelli 26 Jul '14

26 Jul '14

Helo to all, thanks a LOT for your great work! I'm trying to use the x64 library for VS 2013 (12), but I have a lot of "unresolved errors" when I try to compile the *LibLas *library that uses boost. For example I get this error: *error LNK2001: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::system_category(void)" (?system_category@system@boost@@YAAEBVerror_category@12@XZ)* Could you maybe help me or give some hint? Thanks!!! -- "Il miglior modo per cambiare e iniziare"

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C++ committee meeting report
by Beman Dawes 25 Jul '14

25 Jul '14

The C++ committee met last week in Rapperswil, Switzerland. Actions that might be of interest to Boosters include: * Shipped the File System TS for ISO DTS (i.e. final) ballot. Since it would be very unusual for at DTS ballot to fail, the File System TS is essentially done. The committee is now actively looking for File System TS 2 proposals. My work now shifts to bringing the Boost implementation into compliance. * Shipped the Library Fundamentals TS for ISO PDTS (i.e. preliminary) ballot. This TS includes Boost.Any and Boost.Optional. * Voted to start work Library Fundamentals TS 2. The plan is to issue a continuing stream of Library Fundamentals TSes, with work starting on the next TS as soon as content for the current TS freezes. Hopefully Boost developers will submit proposals for this TS too. It will be a good home for small libraries that don't need a whole TS of their own. * Shipped the C++ Extensions for Parallelism TS for ISO PDTS (i.e. preliminary) ballot. * The Library Evolution Working Group (LEWG) voted to base the Networking TS on Boost.ASIO. That was a major surprise, as a Networking Study Group had been trying to build up a Networking TS from many small proposals. But in LEWG polls, support for ASIO was overwhelming, with no one at all voting against. This was a major vote of confidence for Boost.ASIO and Chris Kohlhoff. And several ASIO supporters were not even in the room at the time because Filesystem issues were being worked on elsewhere. The next C++ committee meeting is November 3rd to 8th in Urbana-Champaign, IL, USA. As always, Boosters welcome. --Beman

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[rational] Inadvertent construction from double
by Andrzej Krzemienski 25 Jul '14

25 Jul '14

Hi, I have encountered something I consider a bug in boost::rational's interface. Its documentation discusses in detail why conversion from double is not supported, but the following code works fine: #include <iostream> #include <boost/rational.hpp> int main() { double d = 31.82; boost::rational<int> r = d; std::cout << r << std::endl; } With the following result: 31/1 It just discards the fractional part. Such conversion is really confusing an I claim should be explicitly deleted. Regards, &rzej

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Use of third-party libraries
by Michael Shepanski 25 Jul '14

25 Jul '14

On one hand, there's this: "A Boost library *should not* use libraries other than Boost or the C++ Standard Library." (http://www.boost.org/development/reuse.html) On the other hand, sometimes it just seems like common sense. E.g. Boost.Math uses NTL, MPFR, and others. Now I'm trying to get quince and its backend libraries (quince_postgresql, quince_sqlite) into shape for blincubator. The job of the backends is to liaise between quince and other people's libraries: libpq and sqlite3. There is no getting around that. So I was hoping that the prohibition would be waived in this case, as it was in the case of Boost.Math. The trouble I have is that quince_postgresql and quince_sqlite are *not* header-only, and their code that calls libpq and sqlite3 is in .cpp files. And yet I don't want them to break the boost build for people who don't need this stuff, and haven't installed either or both of those third-party libraries. Any suggestions? Any precedents? Thanks, --- Michael

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How to establish boost configurations for cross-compilers not currently covered?
by Dave Gomboc 25 Jul '14

25 Jul '14

The boost config manual (http://www.boost.org/doc/libs/1_55_0/libs/config/doc/html/index.html) does not explicitly address the case where one is attempting to determine the relative lack of C++98 compliance of a cross-compiler (e.g., for an embedded system) that is not already within Boost's supported set of compilers. Is there a clear process documented somewhere for how to go about this? If not, I would appreciate any tips. I have more than one cross-compiler that I am interesting in "Boost"ing. Thanks, Dave

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[function_types] synthesis & explicit calling convention
by Domagoj Saric 25 Jul '14

25 Jul '14

I am unable to synthesize a pointer to a function (or a function type) with the fastcall (or any other, explicitly specified) calling convention. MSVC10 SP1: ** #define BOOST_FT_COMMON_X86_CCs #include "boost/function_types/function_pointer.hpp" #include "boost/function_types/property_tags.hpp" causes error C1017: invalid integer constant expression boost\boost_1_55_0\boost\function_types\detail\pp_cc_loop\preprocessed.hpp 28 ** doing #define BOOST_FT_COMMON_X86_CCs 1 (contrary to documentation but suggested in some places) and including #include <boost/function_types/config/config.hpp> fixes the above compiler error but then the actual typedef typename boost::function_types::function_pointer < MyParameterTypeList, boost::function_types::tag<boost::function_types::non_variadic, boost::function_types::fast_cc> >::type MyFunctionPointerType; fails with error C2065: 'fast_cc' : undeclared identifier help..please? :) -- Domagoj Saric Software Architect www.LittleEndian.com

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[type_erasure] call with multiple placeholders
by Benedek Thaler 24 Jul '14

24 Jul '14

Hi, I have the following type erasure setup: https://github.com/erenon/pipeline/blob/type_erasure/include/boost/pipeline… I'd like to make `any` have a method template, `connect_to`, i.e: class any { template <typename T> auto connect_to(const T&) {} } I have a concept, added to the main concept like this: detail::has_connect_to<type_erasure::_self, type_erasure::_a> And also a concept_interface specialization. (Bottom of the file in the link above) The doc says: "When there are multiple placeholders involved, you will have to use tuple, or pass the bindings explicitly, but the substitution still works the same way. " I'm trying to do just like this, but without success. Errors include: error: ‘const struct boost::type_erasure::_self’ has no member named ‘connect_to’ error: ‘apply’ is not a member of ‘boost::pipeline::detail::has_connect_to<boost::type_erasure::_self, boost::type_erasure::_a>’ *error: no matching function for call to ‘call(boost::type_erasure::concept_interface<...[snip]...>`* I think the last one is the core issue, but I can't figure out how to pass the binding properly. I don't know why does concept_interface show up as the first argument. Thanks, Benedek

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[xpressive] capture float?
by Greg Rubino 24 Jul '14

24 Jul '14

Hi all, I'm trying to capture a float with xpressive and put it into a local map. As a simplified example, I tried just pushing the matched pattern to a float and the result is always a float containing '0'. namespace xpr = boost::xpressive; std::map<float, std::string> l_floatOperMap; xpr::sregex l_relation = xpr::as_xpr("<=") | ">=" | "<" | ">"); l_floatRestriction = !(xpr::s1 = l_relation) >> (xpr::s2 = (+xpr::_d >> '.' >> +xpr::_d)) [xpr::ref(l_floatOperMap)[xpr::as<float>(xpr::s2)] = xpr::as<std::string>(xpr::s1)]; However, when I go to print the contents of l_floatOperMap, it contains only the tuple (0, ""). Is it something I'm doing wrong? It seems like this should work to me. Thanks, Greg

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[Boost Library Incubator] Unable to submit library
by Edward Diener 22 Jul '14

22 Jul '14

I tried to submot a library to the Boost Library Incubator only to get a parsing error message followed by absolutely nothing happening no matter how many times I attempted to click the Submit button. It is no fun re-entering all that data again.

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