December 2008 - Boost-users

[Proto] Detecting series of operator in grammar
by Joel Falcou 03 Dec '08

03 Dec '08

How can I write a transform that matches expression like a0+a1+a2+ ... +an (with N +) and turn into a custom node like sum(a0,a1,...,an) Thanks in advance -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

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Re: [Boost-users] [review][constrained_value] Review of ConstrainedValue Library begins today
by raindog＠macrohmasheen.com 03 Dec '08

03 Dec '08

Another example: 6 represents june. 6 + 3 is then 3 months after june, otherwise september. 6 + 12 is the next june. ------Original Message------ From: Edward Diener Sender: boost-users-bounces(a)lists.boost.org To: boost-users(a)lists.boost.org Cc: boost(a)lists.boost.org ReplyTo: boost-users(a)lists.boost.org Sent: Dec 3, 2008 8:03 PM Subject: Re: [Boost-users] [review][constrained_value] Review of ConstrainedValue Library begins today Deane Yang wrote: > Edward Diener wrote: >> Deane Yang wrote: >>> >>> I have an even more extreme view on this. I don't believe any >>> arithmetic operations should be permitted for constrained numbers. >>> They just don't make sense (would you ever want to add two different >>> days of a month?). >> >> You have chosen a particular type for which arithmetic operations >> sometimes make little sense. In many other situations this is not the >> case. > > > Could you give an example? An example of what ? Of a constraint where arithmetic operations make sense ? If we take a constraint representing a percentage between 0 and 100, I think it is perfectly valid to add a percent to what is already there. That is just one of innumerable cases where arithmetic operations of contraints seem perfectly valid to me. Why would you even want to consider limiting constraints by removing arithmetic operations if the underlying type supports such operations ? _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users Sent from my Verizon Wireless BlackBerry

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Re: [Boost-users] [review][constrained_value] Review of ConstrainedValue Library begins today
by raindog＠macrohmasheen.com 03 Dec '08

03 Dec '08

I totally agree. Pre contstraining a value for assignment to constrained_value seems to defeat the purpose of the library all together. ------Original Message------ From: Edward Diener Sender: boost-users-bounces(a)lists.boost.org To: boost-users(a)lists.boost.org Cc: boost(a)lists.boost.org ReplyTo: boost-users(a)lists.boost.org Sent: Dec 3, 2008 7:58 PM Subject: Re: [Boost-users] [review][constrained_value] Review of ConstrainedValue Library begins today Mathias Gaunard wrote: > Edward Diener wrote: > >> I disagree with your analysis. The '26' value could be a run-time >> calculation and not just a compile-time constant. In which case you >> are saying that the assignment of a run-time calculation should assert >> only when run in debug mode and otherwise should be ignored. I can not >> agree with that idea. > > I say it is up to the programmer to ensure valid values are provided. > If the value is only known at runtime, there should be explicit checking > in the code prior to assignment. Suppose the value is provided by the end user of the program. Do you still feel such a value, when used in a constraint, should assert only in debug mode rather than throw an exception ? A large part of the constrained value concept is that the constraint provides the necessary checking, in the form of a policy, which alleviates specific pre-checking by the programmer. I like that, else the constraint library serves less purpose than it could. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users Sent from my Verizon Wireless BlackBerry

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How to pass a shared_ptr to a thread.
by Jason Cipriani 03 Dec '08

03 Dec '08

Hi, I'm new to boost. I'm using it for the shared_ptr implementation. I have a usage question. On Windows, a thread function takes a void* parameter. If I have a shared_ptr to an object, what's the correct way to pass that to a new thread? E.g.: DWORD WINAPI threadproc (LPVOID something) { // how to get a shared_ptr through "something"? ... } void create5threads () { ... shared_ptr p(new Object); // what should "something" be if i want to pass p to the new threads, incrementing its use count? CreateThread(..., &threadproc, (LPVOID)something, ...); CreateThread(..., &threadproc, (LPVOID)something, ...); CreateThread(..., &threadproc, (LPVOID)something, ...); CreateThread(..., &threadproc, (LPVOID)something, ...); CreateThread(..., &threadproc, (LPVOID)something, ...); } Sorry if this is a stupid question, but the only thing I could think of was "(LPVOID)new shared_ptr(p)", but that means each thread must explicitly delete the new shared_ptr and that kind of defeats the purpose! Thanks, Jason

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Questions about Program_options
by Yang Zhang 03 Dec '08

03 Dec '08

Hi, I'm currently enjoying using Program_options, and I have a few questions/comments about it. Is it necessary to create and use a variable_map for parsing program options? Is there a way to forgo this if I've already used value<T>(T*) to bind the options to other storage locations? What is notify() for, exactly? This is not really described in the documentation. It may be worth mentioning bool_switch somewhere in the documentation. (I dug this up from the header files.) Can I access positional arguments without going through the positional_options_description? My program is "variadic" and takes either 1 or 2 arguments (where the first has a completely different meaning depending on the number of args). I realize I can assign meaningless names in the positional_options_description, like "arg0," "arg1," etc., but I'm just wondering if there's already a way to access the raw positional arguments without going through the positional_options_description boilerplate. Is there a way to specify a *hierarchy* of command-line parameters, such as those found in svn (a two-layer hierarchy), git, etc.? If not, consider this a feature request! In svn, for instance, there are global options, there's the exact command, and then there are sub-options associated with the command. See the Python argparse module for an example of such a library design: http://argparse.python-hosting.com/ Thanks in advance for any answers. -- Yang Zhang http://www.mit.edu/~y_z/

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[program_options] split_winmain
by Vitaly Grechko 03 Dec '08

03 Dec '08

>Vitaly Grechko wrote: >> Could _WIN32 be removed from program_options\parsers.hpp? There is no way in >> UNIX to parse command line independently from string. To use the library I >> had to dublicate parsers.hpp and winmain.cpp files localy with _WIN32 >> removed, which is ugly. Before this I tryed to define _WIN32 before >> including parsers.hpp and undef after - this affected other boost headers >> and did not compile. >> I don't see the reason to have _WIN32 macro there because the code is just >> an algorithm and complied successfuly in all platforms. The meaning of the >> algorithm is in the name of the function 'split_winmain(...)'. >> The use case example: command lines from Windows client machines go to Unix >> server for validation and logging. In this case split_winmain is regularly >> used on UNIX >What 'validation and logging' can be possibly done on Linux, given Windows command >line? Why do you need to actually tokenize it? >- Volodya (Sorry for broken thread, It is my first message and I was a digest user and Gmane does not contain my message) Command lines can be sent by network from Windows to Linux program which processes it and send back some result (client/server system). But this is just a straightforward example. Other example: There is a tool that is compiled on Windows and Linux. It does not have argc, argv because command line is entered say in editbox. The tool should parse this line and the algorithm should be the same in all operating systems to have single behavior. In my case the user specifies a command line as an argument to a function in script file. Probably it is safe to allow using split_winmain in UNIX to avoid the hell described in previous message.

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path separator char/string
by boost001 03 Dec '08

03 Dec '08

I need to get the char or string represent current system's path separator. In ACE , we can get from this constant: ACE_DIRECTORY_SEPARATOR_CHAR. Does Boost has the similar constant to do the same? I looked at the path.hpp. I think maybe I can get it from the following existing code: 1. template<class Path> struct slash { BOOST_STATIC_CONSTANT( char, value = '/' ); }; 2. # ifdef BOOST_WINDOWS_PATH template<class Path> struct path_alt_separator { BOOST_STATIC_CONSTANT( char, value = '\\' ); }; # endif 3. template<class Path> inline bool is_separator( typename Path::string_type::value_type c ) { return c == slash<Path>::value # ifdef BOOST_WINDOWS_PATH || c == path_alt_separator<Path>::value # endif ; } But I don't know exactly how. Anybody can help me? -- View this message in context: http://www.nabble.com/path-separator-char-string-tp20820786p20820786.html Sent from the Boost - Users mailing list archive at Nabble.com.

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[boost][serialization] void_upcast is very slow
by Jacob 03 Dec '08

03 Dec '08

The original "inline void_upcast" method checks if the pointer to the object is of the right type, by traversing its parents. This is necessary when using multiple inheritance, since in such a case the adress of the pointer to the object can vary depending on which base class it is cast to. While profiling one of my projects I noticed that most of the time was spent in the void_upcast method. I modified the method to return the pointer directly(see below), resulting in a high performance increase. This "solution" is possible if you avoid multiple inheritance all together, which I did. In my particular project I experienced a 75% speed increase implementing this, going from about 10 seconds to 2.5 seconds. Would it be possible to implement some functionality to turn on and off the upcasting for given classes, kind of like the tracking of objects is currently administrated? Modified "inline void_upcast": /inline void * void_upcast( extended_type_info const & derived, extended_type_info const & base, void * const t ){ return const_cast<void*>(t); }/ Yours sincerely, Jacob Holm

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[FILESYSTEM]:Link problem
by Ken zhang 03 Dec '08

03 Dec '08

Hi Dear all I can't link my program with boost::filesystem, the compiler report error below: ..\binaries\lib\libresourcemanager_d.a(resimg.o):resimg.cpp:(.text$_ZN5boost10filesystem6existsINS0_10basic_pathISbIwSt11char_traitsIwESaIwEENS0_12wpath_traitsEEEEENS_9enable_ifINS0_13is_basic_pathIT_EEbE4typeERKSB_[boost::enable_if<boost::filesystem::is_basic_path<boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> >, bool>::type boost::filesystem::exists<boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> >(boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> const&)]+0x77): undefined reference to `boost::filesystem::detail::status_api(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, boost::system::error_code&)' ..\binaries\lib\libresourcemanager_d.a(resimg.o):resimg.cpp:(.text$_ZN5boost10filesystem6detail10path_proxyERKSbIwSt11char_traitsIwESaIwEESt13_Ios_Openmode[boost::filesystem::detail::path_proxy(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, std::_Ios_Openmode)]+0xa8): undefined reference to `boost::filesystem::detail::create_file_api(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, std::_Ios_Openmode)' ..\binaries\lib\libresourcemanager_d.a(resimg.o):resimg.cpp:(.text$_ZN5boost10filesystem6detail10path_proxyERKSbIwSt11char_traitsIwESaIwEESt13_Ios_Openmode[boost::filesystem::detail::path_proxy(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, std::_Ios_Openmode)]+0x143): undefined reference to `boost::filesystem::detail::narrow_path_api(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&)' ..\binaries\lib\libresourcemanager_d.a(resimg.o):resimg.cpp:(.text$_ZN5boost10filesystem6detail10path_proxyERKSbIwSt11char_traitsIwESaIwEESt13_Ios_Openmode[boost::filesystem::detail::path_proxy(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, std::_Ios_Openmode)]+0x1f8): undefined reference to `boost::filesystem::detail::remove_api(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&)' ..\binaries\lib\libresourcemanager_d.a(resimg.o):resimg.cpp:(.text$_ZN5boost10filesystem9file_sizeINS0_10basic_pathISbIwSt11char_traitsIwESaIwEENS0_12wpath_traitsEEEEENS_9enable_ifINS0_13is_basic_pathIT_EEyE4typeERKSB_[boost::enable_if<boost::filesystem::is_basic_path<boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> >, unsigned long long>::type boost::filesystem::file_size<boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> >(boost::filesystem::basic_path<std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >, boost::filesystem::wpath_traits> const&)]+0x6b): undefined reference to `boost::filesystem::detail::file_size_api(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&)' My boost version: 1.37 build script: bjam toolset=gcc --build-type=minimal link=shared stage Mingw32:tdm-mingw-1.808.3-f2 GCC:gcc version 4.3.2 (4.3.2-tdm-1 for MinGW) boost_system-mgw43-mt-1_37.lib boost_iostreams-mgw43-mt-1_37.lib boost_filesystem-mgw43-mt-1_37.lib The same code worked fine on VC2008. Best regards Ken

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[Threads] error building 1.37.0 on cygwin with g++ 4.3.2
by frederic.bron＠alcan.com 03 Dec '08

03 Dec '08

I tried to build 1.37.0 with g++ 4.3.2 on cygwin. Got the following error. Is there a workaround for this or should I go back to g++ 3.4.4? Regards, F. Bron "g++-4" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -DBOOST_POSIX_API -DBOOST_POSIX_PATH -mfpmath=sse -march=pentium-m -mthreads -DBOOST_ALL_NO_LIB=1 -DBOOST_THREAD_BUILD_LIB=1 -DBOOST_THREAD_POSIX -DNDEBUG -I"." -c -o "bin.v2\libs\thread\build\gcc-4.3.2\release\link-static\threading-multi\exceptions.o" "libs\thread\src\pthread\exceptions.cpp" In file included from ./boost/thread/detail/platform.hpp:17, from ./boost/thread/detail/config.hpp:20, from libs\thread\src\pthread\exceptions.cpp:7: ./boost/config/requires_threads.hpp:29:4: error: #error "Threading support unavaliable: it has been explicitly disabled with BOOST_DISABLE_THREADS" ...failed gcc.compile.c++ bin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi/exceptions.o... gcc.compile.c++ bin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi/once.o "g++-4" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -DBOOST_POSIX_API -DBOOST_POSIX_PATH -mfpmath=sse -march=pentium-m -mthreads -DBOOST_ALL_NO_LIB=1 -DBOOST_THREAD_BUILD_LIB=1 -DBOOST_THREAD_POSIX -DNDEBUG -I"." -c -o "bin.v2\libs\thread\build\gcc-4.3.2\release\link-static\threading-multi\once.o" "libs\thread\src\pthread\once.cpp" In file included from ./boost/thread/detail/platform.hpp:17, from ./boost/thread/once.hpp:12, from libs\thread\src\pthread\once.cpp:7: ./boost/config/requires_threads.hpp:29:4: error: #error "Threading support unavaliable: it has been explicitly disabled with BOOST_DISABLE_THREADS" ...failed gcc.compile.c++ bin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi/once.o... gcc.compile.c++ bin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi/thread.o "g++-4" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -DBOOST_POSIX_API -DBOOST_POSIX_PATH -mfpmath=sse -march=pentium-m -mthreads -DBOOST_ALL_NO_LIB=1 -DBOOST_THREAD_BUILD_LIB=1 -DBOOST_THREAD_POSIX -DNDEBUG -I"." -c -o "bin.v2\libs\thread\build\gcc-4.3.2\release\link-static\threading-multi\thread.o" "libs\thread\src\pthread\thread.cpp" In file included from ./boost/thread/detail/platform.hpp:17, from ./boost/thread/detail/config.hpp:20, from libs\thread\src\pthread\thread.cpp:8: ./boost/config/requires_threads.hpp:29:4: error: #error "Threading support unavaliable: it has been explicitly disabled with BOOST_DISABLE_THREADS" libs\thread\src\pthread\thread.cpp: In function 'void boost::this_thread::sleep(const boost::system_time&)': libs\thread\src\pthread\thread.cpp:354: error: 'to_timespec_duration' was not declared in this scope ...failed gcc.compile.c++ bin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi/thread.o... ...skipped <pbin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi>libboost_thread-mt.a(clean) for lack of <pbin.v2/libs/thread/build/gcc-4.3.2 /release/link-static/threading-multi>thread.o... ...skipped <pbin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi>libboost_thread-mt.a for lack of <pbin.v2/libs/thread/build/gcc-4.3.2 /release/link-static/threading-multi>thread.o... ...skipped <p/cygdrive/d/Softs/boost_cyg/lib>libboost_thread-mt.a for lack of <pbin.v2/libs/thread/build/gcc-4.3.2/release/link-static/threading-multi>libboost_thread-mt.a... Avis : Ce message et toute pièce jointe sont la propriété d'Alcan et sont destinés seulement aux personnes ou à l'entité à qui le message est adressé. Si vous avez reçu ce message par erreur, veuillez le détruire et en aviser l'expéditeur par courriel. Si vous n'êtes pas le destinataire du message, vous n'êtes pas autorisé à utiliser, à copier ou à divulguer le contenu du message ou ses pièces jointes en tout ou en partie. Notice: This message and any attachments are the property of Alcan and are intended solely for the named recipients or entity to whom this message is addressed. If you have received this message in error please inform the sender via e-mail and destroy the message. If you are not the intended recipient you are not allowed to use, copy or disclose the contents or attachments in whole or in part.

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