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Is there any corresponding C++ component for java.lang.reflect?
by Bo Xie 22 Aug '06

22 Aug '06

Hi all, I know C++ language does not support Java language's "reflect" mechanism. Is there any corresponding C++ component/library for java.lang.reflect? e.g., Does Boost support "reflect"? Thanks! Best Regards, Xie, Bo

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segfault and no segfault with 2 different boost versions.
by Thierry Dumont 22 Aug '06

22 Aug '06

I develop a C++ code which uses boost::threads * This code performs perfectly well with the boost library wich comes with Debian sarge (libboost-thread1.32.0 for thread library). But I want a more complete implementation of boost (I want to use property tree library). So I have installed and compiled boost_1_33_1. * Using this library, all the programs which use the thread library segfault (at thread-create). Where is the problem ? With the Debian sarge library, I compile with the options: -DBOOST_HAS_THREADS -D_REENTRANT -O2 -funroll-all-loops -fomit-frame-pointer Do I need to change something? Did I missed something when I installed boost_1_33_1? In both cases, g++ version is 3.3.5. -- Thierry Dumont. Institut Camille Jordan -- Mathematiques-- Univ. Lyon I,43 Bd du 11 Novembre 1918, 69622 - Villeurbanne Cedex - France. Thierry.Dumont(a)maply.univ-lyon1.fr web: http://maply.univ-lyon1.fr/~tdumont

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Problem while installin boost 1.33.1
by Leonardo José Reyes Diago 22 Aug '06

22 Aug '06

Hello, i´m trying to install boost 1.33.1, ii'm using windowsXP with visual c++ 2005 express, and using the follow command line: bjam "-sTOOLS=vc-8_0" "—prefix=d:\" install. that have to build a folder with the libraries, but does not do that. This is a part of the message that it show in the command prompt: CALL "C:\Archivos de programa\Microsoft Visual Studio 8\Common7\Tools..\..\VC\bin\vcvars32.BAT" >nul "C:\Archivos de programa\Microsoft Visual Studio 8\Common7\Tools..\..\VC\bin\cl" /Zm800 -nologo /EHsc -c -DBOOST_DATE_TIME_STATIC_LINK -DUSE_DATE_TIME_PRE_1_33_FACET_IO /Z7 /Od /Ob0 /EHsc /GR /MTd /Zc:forScope /Zc:wchar_t -I"bin\boost\libs\date_time\build" -I"C:\boost_1_33_1" -Fo"bin\boost\libs\date_time\build\libboost_date_time.lib\vc-8_0\debug\runtime-link-static\threading-multi\greg_month.obj" -Tp"C:\boost_1_33_1\libs\date_time\build\../src/gregorian/greg_month.cpp" ...failed vc-C++ bin\boost\libs\date_time\build\libboost_date_time.lib\vc-8_0\debug\runtime-link-static\threading-multi\greg_month.obj...vc-C++ bin\boost\libs\date_time\build\libboost_date_time.lib\vc-8_0\debug\runtime-link-static\threading-multi\greg_weekday.obj The system cannot find the specified route . The system cannot find the specified route . ...skipped <@boost!lib>libboost_wave-vc80-mt-1_33_1.lib for lack of <@boost!libs!wave!build\libboost_wave.lib\vc-8_0\release\threading-multi>libboost_wave-vc80-mt-1_33_1.lib... ...skipped <@boost!lib>boost_date_time-vc80-mt-gd.lib for lack of <@boost!lib>boost_date_time-vc80-mt-gd-1_33_1.lib... ...skipped <@boost!lib>boost_date_time-vc80-mt.lib for lack of <@boost!lib>boost_date_time-vc80-mt-1_33_1.lib... ...skipped <@boost!lib>libboost_date_time-vc80-mt-sgd.lib for lack of <@boost!lib>libboost_date_time-vc80-mt-sgd-1_33_1.lib... ...failed updating 808 targets... ...skipped 336 targets... ...updated 2 targets... Can someone help me to solve this? Thanks

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Boost regex multi-processor scalability and user-defined allocators
by Roy Emek 22 Aug '06

22 Aug '06

Iâm using boost-regex library, and Iâm running into multi-threading scalability issues. When tested on a machine with several CPUs, my performance tests show improvement of about 60-70% when moving from a single thread to 2 threads. Question 1: Is anyone aware of this problem? Is there a known solution? >From some testing weâve done, it seems that the cause of the scalability issue is problematic implementation of std:allocator. This is a known issue on some operating systems (e.g., Solaris 8). Some of the boost::regex classes (e.g., match_results) accept a user-defined allocator. However, as far as I can understand thereâs no way to completely override the use of std::allocator. Question 2: is there a way to completely prevent boost / regex from using std::allocator? If no, can such a capability be added? (One solution to this problem would be global overriding the ânewâ and âdeleteâ operators â but for various reasons this cannot be done in the application Iâm developing). __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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Re: [Boost-users] [Signals] Relationships to other libraries and terms
by Ames Andreas 22 Aug '06

22 Aug '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Scott Meyers > Sent: Tuesday, August 22, 2006 12:07 AM > Subject: [Boost-users] [Signals] Relationships to other > libraries and terms > > We start with "callable entities" -- things that can be called, e.g., > function pointers, function objects, bound member functions, > etc. As I > understand it: > > - A callback (function or object) is a callable entity > - A slot in Boost.Signals is a callable entity > - boost::bind and boost::lambda create callable entities. > - A boost::function object stores a callable entity. > > We also have collections of callable entities: > > - A .NET delegate is a collection of 0 or more callable > entities with a > given signature. > - A signal in Boost.Signals is a collection of 0 or more callable > entities with signatures compatible with a given signature. > > Objects of these collection types are also callable entities: > > - When a Boost.Signals signal or a .NET delegate is > called, it invokes > the callable entities it contains. > > Is that correct? > > Also, does anybody know where the name "slot" comes from in > this context? > I've found this term to be a stumbling block for trying to > understand this > stuff. I think the callability of signals is just a detail. Libsigc++ seems to prefer signal.emit() (although they also have operator()). A slot corresponds to the Observer (in the corresponding GoF pattern), i.e the receipient of a signal (which comes closest to the subject in the GoF pattern). Regarding the terminology: IIRC, it was introduced by a signal/slot lib in C, unfortunately I can't find the links, sorry (I'd also be interested in them, if anyone can find them). There are quite some implementations in C++: Qt, libsigc++, boost and others. On the libsigc++ mailing list was a discussion about the terminology, you can find it in the thread starting with http://mail.gnome.org/archives/libsigc-list/2005-July/msg00014.html. cheers, aa -- Andreas Ames | Programmer | Comergo GmbH | Voice: +49 69 7505 3213 | ames AT avaya DOT com

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Problem binding a predicate to random_shuffle()
by Nelis Franken 22 Aug '06

22 Aug '06

Good day. After an initial post on the comp.lang.c++ usergroup, I was pointed to using boost::bind for binding member functions as predicates for STL functions (original example applied to sort()). The technique to use Boost's bind() works well, except when used with STL's random_shuffle(). The following code demonstrates a working call (on sort()) and a call that generates an error (on random_shuffle()), both using the same technique. The code: #include <algorithm> #include <functional> #include <vector> #include <boost/bind.hpp> using namespace std; class Foo { public: Foo() { for (int i=0; i < 5; i++) { dataVector.push_back(i*10); idVector.push_back(i); } } bool isLess(int leftID, int rightID) { return (dataVector[leftID] < dataVector[rightID]); } int customRand(int n) { return (rand() % n); } void mySort() { sort(idVector.begin(), idVector.end(), boost::bind(&Foo::isLess, this, _1, _2)); } void myShuffle() { random_shuffle(dataVector.begin(), dataVector.end(), boost::bind(&Foo::customRand, this, _1)); } private: vector<int> dataVector; vector<int> idVector; }; int main(int argc, char** argv) { Foo myObj; myObj.myShuffle(); myObj.mySort(); return 0; } The error: sort.cpp: In member function `void Foo::myShuffle()': sort.cpp:33: error: no matching function for call to `random_shuffle(__gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >, __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >, boost::_bi::bind_t<int, boost::_mfi::mf1<int, Foo, int>, boost::_bi::list2<boost::_bi::value<Foo*>, boost::arg<1> > >)' /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_algo.h:1766: note: candidates are: void std::random_shuffle(_RandomAccessIterator, _RandomAccessIterator, _RandomNumberGenerator&) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >, _RandomNumberGenerator = boost::_bi::bind_t<int, boost::_mfi::mf1<int, Foo, int>, boost::_bi::list2<boost::_bi::value<Foo*>, boost::arg<1> > >] The code compiles and runs fine using VC7.1 (Visual Studio 2003), but gives an error using g++ (GCC) 3.4.4 (cygming special). Any help will be greatly appreciated. Kind regards, Nelis Franken PS: A follow-up post on the exact same problem to comp.lang.c++ directed me to post it on the Boost list, since it was deemed off-topic. I hope someone else on this list has had a similar STL problem with random_shuffle() and boost::bind?

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[Format] Why boost::format doesn't work with /vd2 compiler option?
by SMART_n 22 Aug '06

22 Aug '06

Hello. I have a project in Visual Studio 2005. This project uses GtkMM library and it's necessary to use /vd2 compiler option. The problem is that Boost::format doesn't work(raise exception) with this option. What can i do? Is it possible to use boost::format with this compiler option?

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bcbboost 0.5 released
by Nicola Musatti 22 Aug '06

22 Aug '06

Hallo, I just released version 0.5 of bcbboost, a set of patches that enable use of the Boost 1.33.1 libraries with Borland's BCB2006. This is likely to be the last release to be based on this combination of libraries and compiler. As 1.34 will include all the patches included here, I don't expect to issue further releases before a new version of BCB comes out. You can download it from here: http://prdownloads.sourceforge.net/bcbboost/bcbboost-1_33_1-5_8_2-0.5.zip?d… Please post any bug report, suggestion, request for clarification to the project trackers on its SourceForge site: http://sourceforge.net/projects/bcbboost/ Cheers, Nicola Musatti

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SIGABRT (Abort) On Debian with boost::filesystem::path append
by Eric Hill 21 Aug '06

21 Aug '06

Does anyone have any suggestions on how I can fix/diagnose/troubleshoot this little problem? 11 std::cout << "Parsing folder " << folder_name << std::endl; (gdb) n Parsing folder testing 12 boost::filesystem::path folder(folder_name, boost::filesystem::native); (gdb) n 13 boost::filesystem::path message_to = folder / ".to"; (gdb) n Program received signal SIGABRT, Aborted. 0x4040583b in raise () from /lib/tls/libc.so.6 (gdb) TIA, Eric

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[type_traits] Why there is no recursive_const trait?
by Ovanes Markarian 21 Aug '06

21 Aug '06

Hello, I am just wondering why boost does not provide recursive_const type trait? The application would be for Example: recursive_const<T***>::type same as: T const *const *const *const Are there any reasons not to provide this? With Kind Regards, Ovanes Markarian

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