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Re: [Boost-users] dynamic link error: boost::program_options::arg not found (Sebastian Hauer)
by Vial, Florent 18 Sep '08

18 Sep '08

Hi Sebastian and Ovanes, I am facing the same problems as you with linking to boost::program_options, and boost::system too. In all my win32 projects (I use msvc9.0), I define BOOST_DYN_LIB using a common property sheet. It compiles just fine with 1.36.0 but it does not link. I also specify BOOST_LIB_DIAGNOSTIC so that I can see what boost auto link is trying to do. May be I should say that I built my boost 1.36.0 libraries on Win32 (Windows XP Professional SP3) using following command line: ./bjam.exe toolset=msvc --build-type=complete --build-dir="D:\tmp" --threading=multi --runtime-link=static,shared --prefix="C:\boost1.36" install --without-mpi --without-python --without-wave When I compile my project (some libraries using boost_filesystem and boost_system, some not), I can see in the compiler output: Linking to lib file: boost_filesystem-vc90-mt-1_36.lib Linking to lib file: boost_system-vc90-mt-1_36.lib When I compile my main : #include <iostream> #include <boost/program_options.hpp> namespace po = boost::program_options; int main(int argc, char **argv) { int ret = 0; po::variables_map vm; po::options_description all("Allowed options"); try { po::options_description general("General options"); general.add_options() ("help,h", "Show this message and exit.") ("version,v", "Output version information and exit."); po::options_description optional("Optional options"); optional.add_options() ("optional,o", po::value<std::string>(), "Optional") ("optional2,p", po::value<std::string>(), "Optional2"); all.add(general).add(optional); po::store(po::parse_command_line(argc, argv, all), vm); po::notify(vm); } catch (const po::invalid_command_line_syntax &badsyntax) { /* My log error with badsyntax*/ ret = -1; } catch (const po::unknown_option &badoption) { /* My log error with badoption*/ ret = -2; } catch (const po::error &err) { /* My log error with err*/ ret = -3; } if (vm.count("optional")) { std::string optionalParam = vm["optional"].as<std::string>(); /** Handling optionalParam ... */ } if (vm.count("optional2")) { std::string optionalParam2 = vm["optional2"].as<std::string>(); /** Handling optionalParam2 ... */ } if (vm.count("help")) { std::cout << all << std::endl; return 0; } return ret; } with following command line: /O2 /Ob2 /Oy /I all-my-includes-here /I "../../../../boost/include/boost-1_36" /D "BOOST_PROGRAM_OPTIONS_DYN_LINK" /D "UNICODE" /D "NDEBUG" /D "BOOST_LIB_DIAGNOSTIC" /D "BOOST_SYSTEM_DYN_LINK" /D "BOOST_FILESYSTEM_DYN_LINK" /D "BOOST_THREAD_DYN_LINK" /D "NOMINMAX" /D "WIN32_LEAN_AND_MEAN" /D "WIN32" /D "_WINDOWS" /D "_CRT_NONSTDC_NO_WARNINGS" /D "_CRT_SECURE_NO_WARNINGS" /D "_CRT_SECURE_NO_DEPRECATE" /D "_CRT_NONSTDC_NO_DEPRECATE" /FD /EHsc /MD /GS- /arch:SSE2 /Fo"./../../Release/MyApp/" /Fd"./../../Release/MyApp/vc90.pdb" /W3 /nologo /c /TP /wd4100 /wd4290 /errorReport:prompt -EHsc -Zm200 -w34100 -w34189 -w34189 I can see in the compiler output following lines: Linking to lib file: boost_program_options-vc90-mt-1_36.lib ../../../../boost/include/boost-1_36\boost/program_options/errors.hpp(21) : warning C4275: non dll-interface class 'std::logic_error' used as base for dll-interface class 'boost::program_options::error' > C:\Programme\MicrosoftVisualStudio9.0\VC\include\stdexcept(21) : see declaration of 'std::logic_error' > ../../../../boost/include/boost-1_36\boost/program_options/errors.hpp(21) : see declaration of 'boost::program_options::error' >../../../../boost/include/boost-1_36\boost/program_options/errors.hpp(61) : warning C4251: 'boost::program_options::ambiguous_option::alternatives' : class 'std::vector<_Ty>' needs to have dll-interface to be used by clients of class 'boost::program_options::ambiguous_option' > with > [ > _Ty=std::string > ] [snip a lot of similar warnings] Then, linking with following command line /OUT:"../../Release\MyApp.exe" /INCREMENTAL /NOLOGO /LIBPATH:"../../Release" /LIBPATH:"..\..\..\..\boost/lib/vc90" /MANIFEST /MANIFESTFILE:"../../Release/MyApp\MyApp.exe.intermediate.manifest" /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /NODEFAULTLIB:"libcpmt.lib" /NODEFAULTLIB:"libcmt.lib" /SUBSYSTEM:CONSOLE /DYNAMICBASE:NO /MACHINE:X86 /ERRORREPORT:PROMPT msvcrt.lib msvcprt.LIB binmode.obj kernel32.lib user32.lib netapi32.lib Iphlpapi.lib Ws2_32.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib I get following errors: Memain.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall boost::program_options::detail::cmdline::set_additional_parser(class boost::function1<struct std::pair<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &>)" (__imp_?set_additional_parser@cmdline@detail@program_options@boost@@QAEXV?$function1@U?$pair@V?$basic_string@DU?$char_traits@D@std@@V?$alloc ator@D@2@@std@@V12@@std@@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@2@@4@@Z) referenced in function "public: class boost::program_options::basic_command_line_parser<char> & __thiscall boost::program_options::basic_command_line_parser<char>::extra_parser(class boost::function1<struct std::pair<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &>)" (?extra_parser@?$basic_command_line_parser@D@program_options@boost@@QAEAAV123@V?$function1@U?$pair@V?$basic_string@DU?$char_traits@D@std@@V? $allocator@D@2@@std@@V12@@std@@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@2@@3@@Z) 1>metiscalibrationdata.lib(MetisMatrixCalibration_io.obj) : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::get_generic_category(void)" (?get_generic_category@system@boost@@YAABVerror_category@12@XZ) referenced in function "void __cdecl boost::system::`dynamic initializer for 'generic_category''(void)" (??__Egeneric_category@system@boost@@YAXXZ) error LNK2019: unresolved external symbol "__declspec(dllimport) class boost::system::error_category const & __cdecl boost::system::get_generic_category(void)" (__imp_?get_generic_category@system@boost@@YAABVerror_category@12@XZ) referenced in function "void __cdecl boost::system::`dynamic initializer for 'generic_category''(void)" (??__Egeneric_category@system@boost@@YAXXZ) 1>filesystem.lib(FileUtils.obj) : error LNK2001: unresolved external symbol "__declspec(dllimport) class boost::system::error_category const & __cdecl boost::system::get_generic_category(void)" (__imp_?get_generic_category@system@boost@@YAABVerror_category@12@XZ) 1>filesystem.lib(FileUtils.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) class boost::system::error_code boost::filesystem::detail::throws" (__imp_?throws@detail@filesystem@boost@@3Verror_code@system@3@A) referenced in function "void __cdecl boost::filesystem::remove<class boost::filesystem::basic_path<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,struct boost::filesystem::path_traits> >(class boost::filesystem::basic_path<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,struct boost::filesystem::path_traits> const &,class boost::system::error_code &)" (??$remove@V?$basic_path@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@Upath_traits@filesystem@boost@@@filesystem@boost@@@fi lesystem@boost@@YAXABV?$basic_path@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@Upath_traits@filesystem@boost@@@01@AAVerror _code@system@1@@Z) When I open boost\include\boost-1_36\boost\program_options\detail\cmdline.hpp I can see BOOST_PROGRAM_OPTIONS_DECL declared as __declspec(dllimport) when compiling my application. When I open boost\include\boost-1_36\boost\system\error_code.hpp, I can see BOOST_SYSTEM_DECL declared as __declspec(dllimport) as well. So my question (at last!) is: how can I check if those symbols were properly exported when building boost ? thank you, Cheers, Florent ---------------------------------------------------------------------- Message: 1 Date: Wed, 17 Sep 2008 13:21:41 -0400 From: "Sebastian Hauer" <sebastian.hauer(a)gmail.com> Subject: Re: [Boost-users] dynamic link error: boost::program_options::arg not found To: boost-users(a)lists.boost.org Message-ID: <fb92d9f00809171021k8c0cf93i75f67b9564281852(a)mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Hello Ovanes, thanks for the reply. I fixed it. I eventually found your posting and tried your suggestion attributing boost::program_options::arg with an additional __declspec(selectany) but either I did something wrong or things are different with msvc-8.0 it did not work for me. Instead I went down a different path and got rid of the global arg variable altogether. Since nothing seems to write into it and the value is always copied it seemed like a reasonable thing to do considering it causes so much grief with the linking. Once this was fixed I got another linker error: error LNK2001: unresolved external symbol "public: static unsigned int const boost::program_options::options_description::m_default_line_length" (?m_default_line_length@options_description@program_options@boost@@2IB) I found the solution to that one from this posting from Evert at http://archives.free.net.ph/message/20080815.085344.d72efb54.en.html . Once I changed the declaration of the class static const m_default_line_length to: BOOST_STATIC_CONSTANT (unsigned, m_default_line_length = 80); With these two changes in place all compiled and linked without a problem. Below I've inlined the patch of my changes against the original boost_1_36_0 source as reference for other people running into this issue. If these changes seem like a good idea to others perhaps they could be included with the next boost release. Regards, Sebastian

2 1

boost::multi_index help
by Axel 18 Sep '08

18 Sep '08

I'm trying to use multi_index to store objects pointers. These objects have mainly 3 fields : - string name - int id - int block_id name & id are unique among all instances, but block_id can be the same for many instances. I want to distribute the object instances among a few blocks, so many instances can have block_id 0, many others block_id 1, and so on. (there are 6 blocks for the moment) here is my struct : /* tags */ struct name_{} ; struct id_{} ; struct block_id_{} ; typedef hashed_unique< tag<name_>, boost::multi_index::mem_fun<Foo, string, &Foo::getName> > NameIndex ; typedef ordered_unique< tag<id_>, boost::multi_index::mem_fun<Foo, int, &Foo::getId> > IdIndex ; typedef ordered_non_unique< tag<block_id_>, boost::multi_index::mem_fun<Foo, int, &Foo::getBlockId> > BlockIndex ; typedef multi_index_container<Foo*, indexed_by<NameIndex, IdIndex, BlockIndex> > FooList ; The name & id indexes work well but I dont manage to get the Foo* pointers for a given block_id. I m using : foo_list_.get<block_id_>().find(1) to grab the wanted list. My problem is that in the result I have not only Foo instances from the block 1. This is what I get when I try to query for a given block_id : For block 5 : only objects with block_id == 5 For block 4 : objects with block_id == 4 and 5 For block 3 : objects with block_id == 3, 4 and 5 For block 2 : objects with block_id == 2, 3, 4 and 5 and so on. I d like to get only the objects with block_id = 4 when I query the multi_index object on its block_id index. I now wonder if what I want to do can be done with multi_index. Thanks in advance for your help

2 2

Cross-Compile Boost for Embedded Linux
by Richard Ketcham 18 Sep '08

18 Sep '08

Hi everyone, Here is my question: what do I have to do to cross-compile boost with this compiler? Right now, the libraries and files associated with threading are the most important to me. I am starting to work with boost at the behest of a coworker. My goal is to get boost compiled for an embedded linux environment. My current setup includes my desktop running Ubuntu which also hosts the buildroot for the embedded linux environment. I have downloaded boost_1_36_0.tar.bz2 and have extracted it to /usr/local/boost_1_36_0/. For the sake of simplicity, let's say that the compiler for the embedded linux environment resides at .../staging_dir/bin/arm-linux-gcc-4.1.1 Thanks in advance for your help. Rich -- There is nothing more practical than a good theory. James Maxwell

4 11

static reflection
by James Pritts 18 Sep '08

18 Sep '08

On a boost thread a while ago, I saw some code to query for the existence of a member function of a class using SFINAE and BOOST_STATIC. I guess you could call it static reflection. Below is a code snippet that does not work using the aforementioned methods. The culprit is the using Base::operator() statement in the Derived class. Apparently the base class method void operator()(float u) is not part of the type of Derived. This was a shock to me, because you can call the overloaded method from the derived class. I'd appreciate any advice on how to check for the existence of member functions in this scenario. I fear it may be impossible. Thanks! #include <iostream> #include <boost/shared_ptr.hpp> typedef char (&no_tag)[1]; typedef char (&yes_tag)[2]; template <typename Class, typename R, typename Arg1, R(Class::*)(Arg1)> struct HasExactSignature { }; template<typename Class, typename R, typename Arg1> no_tag doesVisitorImplementHelper(...); template<typename Class, typename R, typename Arg1> yes_tag doesVisitorImplementHelper(HasExactSignature<Class, R, Arg1, &Class::operator()>* p=0); template<typename Class, typename R, typename Arg1> struct DoesVisitorImplement { BOOST_STATIC_CONSTANT(bool, value = sizeof(doesVisitorImplementHelper<Class,R,Arg1>(0)) == sizeof(yes_tag)); }; struct Base { void operator()(float u) { std::cout << "aaaa"; } }; struct Derived : public Base { using Base::operator(); void operator()(int u) { std::cout << "bbbb"; } }; int main() { std::cout << DoesVisitorImplement<Derived,void,int>::value << std::endl; std::cout << DoesVisitorImplement<Derived,void,float>::value << std::endl; return 0; }

2 1

dynamic link error: boost::program_options::arg not found
by Sebastian Hauer 17 Sep '08

17 Sep '08

Hi, I am trying to dynamically link one of my *libraries* to boost program_options on windows with msvc-8.0 but linking fails due to a missing symbol. Quickly googling for this problem revealed no resolution to my problem, although it appears other people ran into this issue before. Did anyone resolve it or is everyone linking boost program_options statically? I initially ran into this issue on boost 1_34_1 but have since upgraded to 1_36 hoping it would have gotten fixed with no luck. error LNK2001: unresolved external symbol "class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > boost::program_options::arg" (?arg@program_options@boost@@3V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@A) Here is the link command line: link /NOLOGO /INCREMENTAL:NO /DLL /DEBUG /subsystem:console /out:"foo.dll" /IMPLIB:"foo.lib" /LIBPATH:"..\boost_1_36_0\lib.x86-nt-msvc8" @"foo.dll.rsp" And foo.dll.rsp contains besides the name of my object files also references to the following external import libraries: "boost_date_time-vc80-mt-gd-1_36.lib" "boost_filesystem-vc80-mt-gd-1_36.lib" "boost_program_options-vc80-mt-gd-1_36.lib" "boost_system-vc80-mt-gd-1_36.lib" Thanks, Sebastian

2 2

Is there a parameter to build without compiler version info in the target library name?
by Bill David 17 Sep '08

17 Sep '08

By default, the compiled library have a name like: libboost_thread-gcc41-mt.a but I don't want the gcc41 information in the name as I may need modify my makefile to switch to another environment with gcc4.3. So is there a parameter in bjam to suppress the compiler version info in target library name? Or how will you solve this kind of problem?

3 2

Looking for tangent of an arbitrary 2d curve.
by Atanassov Tervel-PT1672 17 Sep '08

17 Sep '08

Hello, I am looking for code which will approximate the tangent at a point of an arbitrary 2D curve. Does boost have such functionality? Thanks, Tervel Atanassov

1 0

[fusion] How to transform types of fusion::map ?
by Zeljko Vrba 17 Sep '08

17 Sep '08

A very concrete question: I have map<pair<K1, V1>, pair<K2, V2>, ..> as input. How do I produce map<pair<K1, std::vector<V1> >, pair<K2, std::vector<V2>, .. > on output? I do not see an equivalent of LISPs MAPCAR in the list of algorithms.. Is this something that should be done by combining fold and push_back algorithms? If so, I'm currently in the dark on how to do it (no example for the fold metafunction algorithm) === Few more questions now that I'm already posting: - what is the difference between accumulate and fold? - what is the purpose of for_each metafunction when the docs say that it always returns void? (and no side-effects are possible at compile-time) Thanks.

4 4

Problem with iterator_facade
by Robert Dailey 17 Sep '08

17 Sep '08

Hi, I have the following iterator_facade class: class PassIterator : public boost::iterator_facade< PassIterator, Pass, boost::forward_traversal_tag > { public: PassIterator(); PassIterator( Effect const& effect ); private: void increment(); Pass& dereference() const; Pass m_pass; friend class boost::iterator_core_access; }; Note how my Pass object is stored by-value in my PassIterator class. When I attempt to compile this class, it fails because dereference() is const and it is trying to return a reference to a const member. However, if I make dereference() non-const, it still fails because the base class is calling into PassIterator::dereference() through a const member function as well, so dereference() *must* be const in order to be callable by boost. How can I overcome this issue? const_cast? mutable? Thanks.

3 5

[EnableIf?] Seeking an example....
by Robert Jones 17 Sep '08

17 Sep '08

Somewhere in the Boost headers, or maybe the Boost documentation I have seen a bit of code which uses SFINAE, and also possibly the enable_if header to select either a find class method or find global template depending on what's available. It might have been written by Eric. I can't find it now,maybe it's not there any more, but if anyone can point me to it I'd really appreciate it! Thanks in advance, - Rob.

3 2

Tuples: Can someone help me generalize this?
by Derrick Hathaway 17 Sep '08

17 Sep '08

Hello, boost-users, what I am trying to accomplish is a generic collection of N objects of type Type. I need for the N objects to be tightly packed and I would like the collection to be constructible in this way: uniform_vector<3, float> my_point(1.0f, 2.1f, 3.2f); I'm very new to the template (meta)programming scene and I would like to get better at it, so any advice you could give that would be instructive in that regard would be much appreciated. The code below is what I have come up with. Question 1: Am I reinventing the wheel at all? In other words is there something I can just typedef to get this functionality? Question 2: If not, how could I generalize this? Is there a template metaprogramming way? I'm sure it can be done with the preprocessor but I'm no good with macros... but then again I'm not much good with templates either at least not by a boost mailing list standard anyway. :) Thanks, Derrick. // -- uniform_vector.hpp ------------------------------------------------------------------------ #ifndef DJH_UNIFORM_VECTOR_HPP #define DJH_UNIFORM_VECTOR_HPP #include <boost/tuple/tuple.hpp> namespace djh { template <unsigned int N, class Type> struct uniform_vector; template <class Type> struct uniform_vector<0, Type>; template <class Type> struct uniform_vector<1, Type> { static const unsigned int size = 1; typedef boost::tuple<Type> type; }; template <class Type> struct uniform_vector<2, Type> { static const unsigned int size = 2; typedef boost::tuple<Type, Type> type; }; template <class Type> struct uniform_vector<3, Type> { static const unsigned int size = 3; typedef boost::tuple<Type, Type, Type> type; }; template <class Type> struct uniform_vector<4, Type> { static const unsigned int size = 4; typedef boost::tuple<Type, Type, Type, Type> type; }; } #endif

2 3

Merging sorted iterators?
by Dr. Roland Bock 17 Sep '08

17 Sep '08

Hi, I have a bunch of iterators over some sorted input from several big files which do not fit into memory. What I would like to have is one iterator which allows me to iterate over the combined sorted input (of course, the result should be sorted, too). Something like this: -------\ --------\ ... ---- --------/ -------/ Is there a class in boost which allows me to do this in a simple way? Thanks and regards, Roland

3 2

[filesystem] Strange problems on Cygwin with 1.36.0
by Boris 17 Sep '08

17 Sep '08

According to http://www.boost.org/doc/libs/1_36_0/libs/filesystem/doc/index.htm#Cgywin Boost.Filesystem seems to be supported on Cygwin. However with the latest version 1.36.0 (which I've built with BOOST_POSIX_API defined) I don't seem to get any Boost.Filesystem function to work on Cygwin. I'm currently running some test cases and had to modify them for Cygwin like this: #if defined(__CYGWIN__) BOOST_CHECK(a == b); #else BOOST_CHECK(bfs::equivalent(a, b)); #endif If a and b contain the very same path you would expect both a == b and boost::filesystem::equivalent() to return true. However on Cygwin boost::filesystem::equivalent() returns false. If I use BOOST_CHECK(bfs::equivalent(a, b)) on Cygwin I get this error: unknown location(0): fatal error in "test_find_param": std::runtime_error: boost::filesystem::equivalent: No such file or directory: "\home\Boris\boost_1_36_0\libs\process\test\..\..\..\bin.v2\libs\process\test\gcc-3.4.4\debug\link-static\runtime-link-static\helpers.exe", "\home\Boris\boost_1_36_0\libs\process\test\..\..\..\bin.v2\libs\process\test\gcc-3.4.4\debug\link-static\runtime-link-static\helpers.exe" Both strings are exactly the same and contain valid Cygwin paths. Is Boost.Filesystem broken on Cygwin? Boris PS: I've a similar problem with boost::filesystem::create_directory() which can't create a directory for no obvious reason.

3 6

[smart_ptr] Problem with circular reference detection
by Jim Barry 17 Sep '08

17 Sep '08

I am trying to detect circular references using the find_unreachable_objects function in sp_collector.cpp. However, it reports false positives in the simple case of one object being owned by another. To illustrate: #define BOOST_SP_ENABLE_DEBUG_HOOKS #include <boost/shared_ptr.hpp> // sp_collector.cpp exported functions std::size_t find_unreachable_objects(bool report); struct X {}; struct Y { boost::shared_ptr<X> pX; Y() : pX(new X) {} }; int main() { boost::shared_ptr<Y> y(new Y); find_unreachable_objects(true); return 0; } The output is as follows: ... 2 objects in m. ... 1 objects in m2. ... 1 objects in open. Unreachable object at 0036BA60, 12 bytes long. Clearly this is incorrect as there are no circular references. Looking at the code, there is what appears to be a typo at line 124: std::cout << "... " << m2.size() << " objects in open.\n"; should be: std::cout << "... " << open.size() << " objects in open.\n"; But the real problem seems to be at line 121: if(p->use_count() != i->second) open.push_back(p); I'm not entirely sure what's going on in this section of code, but it ends up determining (incorrectly) that the "X" object is unreachable. Is there any way to get this working properly? Thanks, - Jim

3 5

Boost Serialize and derived classes
by John Yamokoski 17 Sep '08

17 Sep '08

I can't seem to figure out if what I want is possible. I am using the Boost Serialization library to save the state of my program. I have a manager-type class which holds onto pointers of a base class. The Boost Serialization website has a lot to say about base and derived classes. In a tutorial they show one way to deal with them. But it assumes a priori knowledge of the derived classes: class bus_route { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_route &br); typedef bus_stop * bus_stop_pointer; std::list<bus_stop_pointer> stops; template<class Archive> void serialize(Archive &ar, const unsigned int version) { // in this program, these classes are never serialized directly but rather // through a pointer to the base class bus_stop. So we need a way to be // sure that the archive contains information about these derived classes. //ar.template register_type<bus_stop_corner>(); ar.register_type(static_cast<bus_stop_corner *>(NULL)); // TYPES KNOWN A PRIORI //ar.template register_type<bus_stop_destination>(); ar.register_type(static_cast<bus_stop_destination *>(NULL)); // TYPES KNOWN A PRIORI // serialization of stl collections is already defined // in the header ar & BOOST_SERIALIZATION_NVP(stops); } public: bus_route(){} void append(bus_stop *_bs) { stops.insert(stops.end(), _bs); } }; In my code, however, I don't know exactly what the derived classes might be. The derived objects are created and passed back to my manager class through the base pointer. One option I was considering was that when plugins register with the program, they would have to also register the derived class names with the archive. How this would actually be implemented, I have no idea. Can an archive object be created independently from the Serialization library, modified and then sent back to Serialization? Here is a simple test case I am working on, but I just can't get it to write out the derived classes to file: class base { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(val); } public: base() : val(0.0) {} base(double b) : val(b) {} double val; }; class derived : public base { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { boost::serialization::void_cast_register<derived, base>(static_cast<derived *>(NULL),static_cast<base *>(NULL)); ar & BOOST_SERIALIZATION_NVP(val); } public: derived() : base(0.0), val(0) {} derived(int a, double b) : base(b), val(a) {} int val; }; BOOST_CLASS_EXPORT_GUID(derived, "derived"); class manager { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(objs); } public: std::list<base*> objs; }; void main() { manager mgr; // Creat some data to save derived *d1, *d2, *d3, *d4; d1 = new derived(1, 1.0); d2 = new derived(2, 3.0); mgr.objs.push_back( d1 ); mgr.objs.push_back( d2 ); { std::ofstream ofs("out.xml"); assert(ofs.good()); boost::archive::xml_oarchive oa(ofs); oa << BOOST_SERIALIZATION_NVP(mgr); ofs.close(); } manager new_mgr; { std::ifstream ifs("out.xml"); assert(ifs.good()); boost::archive::xml_iarchive ia(ifs); ia >> BOOST_SERIALIZATION_NVP(new_mgr); ifs.close(); } { std::ofstream ofs("check.xml"); assert(ofs.good()); boost::archive::xml_oarchive oa(ofs); oa << BOOST_SERIALIZATION_NVP(new_mgr); ofs.close(); } delete d1, d2; } I apologize if this commonly asked but I was just looking for some insight as to the best approach. J.D.

2 3

How to implement a reader-writer lock with quick response to writer?
by Bill David 17 Sep '08

17 Sep '08

Question: How to implement a reader-writer lock with quick response to writer? I am using boost1.35.0. I know 1.36.0 is available, but I failed to build regex in 1.36.0 with VC8. I have the following requirements: 1.There are several reader threads and a single writer thread. The writer thread will update shared data periodically. And reader threads may read shared data at any time. 2.As long as writer thread try to update data, all reader thread should be blocked as soon as possible. 3.And reader thread should be blocked during data updating. 4.But reader threads can't be interrupted when they are reading. (i.e. all upcoming reader threads should be blocked, but writer still need wait till the last reader thread in reading finished.) How to implement above scenario with quick response to writer thread? I tried to write the following program to test shared_mutex, but it seems it can't meet my requirement: #include <iostream> using namespace std; #include <boost/thread/shared_mutex.hpp> #include <boost/thread/thread.hpp> #include <boost/thread/xtime.hpp> using namespace boost; boost::shared_mutex rw_mutex; int g_i = 1; void sleep(int iSec) { boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); xt.sec += iSec; boost::thread::sleep(xt); } void read() { while (true) { rw_mutex.lock_shared(); cout << g_i << endl; sleep(3); rw_mutex.unlock_shared(); } } int main() { boost::thread_group threads; for (int i = 0; i < 3; i++) threads.create_thread(read); sleep(1); rw_mutex.lock(); cout << "lock" << endl; g_i = 2; cout << "update g_i to " << g_i << endl; sleep(5); cout << "unlock" << endl; rw_mutex.unlock(); threads.join_all(); } The problem to above solution is it can't respond to writer thread as soon as possible, and only in rare case, it can respond to writer thread in about 6 seconds. The following is a possible output I have gotten: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 lock update g_i to 2 unlock 222 2 2 2 The writer thread should wait no more than 6 seconds, but it seems it can wait more than 20 seconds. Can shared_mutex meet such kind of scenario? If not, do you have any other suggestion?

1 0

Problem serializing unsigned int via save/load
by Diane 16 Sep '08

16 Sep '08

Is there a trick or known bug with serializing an unsigned int via the split free functions? I have a structure that contains an unsigned int, and if I serialize with the free serialize function it works as it should. However, if I split the serialization into save/load I get: boost_1_36_0/boost/archive/detail/iserializer.hpp:541: error: conversion from `boost::serialization::is_wrapper<unsigned int>' to non-scalar type `mpl_::bool_< true>' requested Here's my structure and the two pieces of serialization code: typedef struct CCSTRUCT { unsigned int numRtp; } CCSTRUCT; Serialization #1 (works): template<class Archive> void serialize(Archive & ar, CCSTRUCT& it, const unsigned int version) { ar & it.numRtp; } Serialization #2 (doesn't work): BOOST_SERIALIZATION_SPLIT_FREE(CCSTRUCT) template<class Archive> void save(Archive & ar, const CCSTRUCT& d, unsigned int /* version */) { ar << d.numRtp; } template<class Archive> void load(Archive & ar, const CCSTRUCT& d, unsigned int /* version */) { ar >> d.numRtp; } I need to split the serialization because there are other elements in the structure that can't be handled in serialize(), so I would really appreciate some help if anyone has any ideas. Thanks, Diane

2 1

boost::signal performance in boost 1.36 and VS2005
by Hansi 16 Sep '08

16 Sep '08

Hello, I have made now a small test and I don't know if I make something wrong. I have the following performance comparsion between a boost::function and a boost::signal. Okay, I know that boost::signal has a lot of more functionality and for that it is for sure slower than boost::function. But 100times slower? May be I do something wrong? On my pc I have for boost::function a runtime of 728ms and for boost::signals a runtime of 64128ms There is one slot used for signals. Can anyone give me some hint what I do wrong? my test program was: class TestBind { public: int counter; void OnEventReceived(char b) { counter++; } }; class TestSignal { public: int counter; void OnEventReceived(char b) { counter++; } }; int _tmain(int argc, _TCHAR* argv[]) { TestBind testBind; PerformanceCounter timer; boost::function<void (char)> f = boost::bind(&TestBind::OnEventReceived,&testBind,_1); for(int i = 0; i < 100000000; i++) { f('a'); } TestSignal testSignal; boost::signal<void (char)> sig; sig.connect(boost::bind(&TestSignal::OnEventReceived,&testSignal,_1));; for(int i = 0; i < 100000000; i++) { sig('a'); } } Best regards Hansjörg

1 0

[serialization] Crashes after termination of main()
by Ruediger Berlich 16 Sep '08

16 Sep '08

Hi there, I am consistenty getting crashes in line 80 of the file /opt/boost136/include/boost-1_36/boost/serialization/extended_type_info_typeid.hpp , when my program exits. This is the destructor of class extended_type_info_typeid : ~extended_type_info_typeid(){ type_unregister(); } Any idea of what this is ? I'm using several singletons in my program, which according to their nature, only terminate once main() has finished. They refer to several objects which can, in other contexts, also be serialized. This specific program, however, does not make use of this option. I am pretty sure that the singletons do not refer to each other (any more) as, while searching for the problem, I have redesigned larger portions so that they don't. I'm using Boost 1.36 on OpenSUSE 11 / 64 bit (g++ 4.3.1). Thanks in any case and best regards, Ruediger

3 4

overloading on keyword signature
by e r 16 Sep '08

16 Sep '08

hi, i'm following up on an earlier of my posts with a simpler example. in the example below: the overload is on argument-name and type, yet the overload is ambiguous. 1) is there a way around this? and if so, 2) is it also possible to have an overload the on argument-name only (replace string and int below by *). thanks. *.hpp namespace lib{ BOOST_PARAMETER_NAME(name) BOOST_PARAMETER_NAME(index) BOOST_PARAMETER_FUNCTION( (void), f, tag, (required (name,(std::string))) ) { std::cout << name << std::endl; } BOOST_PARAMETER_FUNCTION( (void), f, tag, (required (index,(int))) ) { std::cout << index << std::endl; } } *.cpp lib::f(lib::_name = "jill"); lib::f(lib::_index = 1); /home/er/cpp/libs/testing_names/par_fun.hpp||In function ‘typename lib::boost_param_result_27f<typename boost::parameter::aux::argument_pack<lib::boost_param_params_27f<int>, const ParameterArgumentType0, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::type>::type lib::f(const ParameterArgumentType0&, typename boost::parameter::aux::match<lib::boost_param_params_27f<int>, ParameterArgumentType0, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::type) [with ParameterArgumentType0 = boost::parameter::aux::tagged_argument<lib::tag::index, const int>]’:| /home/er/cpp/libs/testing_names/main.cpp|28|instantiated from here| /home/er/cpp/libs/testing_names/par_fun.hpp|24|error: call of overloaded ‘boost_param_implf(boost::parameter::aux::arg_list<const boost::parameter::aux::tagged_argument<lib::tag::index, const int>, boost::parameter::aux::empty_arg_list>)’ is ambiguous| /home/er/cpp/libs/testing_names/par_fun.hpp|16|note: candidates are: typename lib::boost_param_result_19f<Args>::type lib::boost_param_implf(const Args&) [with Args = boost::parameter::aux::arg_list<const boost::parameter::aux::tagged_argument<lib::tag::index, const int>, boost::parameter::aux::empty_arg_list>]| /home/er/cpp/libs/testing_names/par_fun.hpp|24|note: typename lib::boost_param_result_27f<Args>::type lib::boost_param_implf(const Args&) [with Args = boost::parameter::aux::arg_list<const boost::parameter::aux::tagged_argument<lib::tag::index, const int>, boost::parameter::aux::empty_arg_list>]| /home/er/cpp/libs/testing_names/par_fun.hpp|24|error: return-statement with a value, in function returning 'void'| ||=== Build finished: 2 errors, 0 warnings ===|

3 2

for_each on boost::ptr_map
by Robert Dailey 16 Sep '08

16 Sep '08

Hi, Is there a way I can use std::for_each() on a boost::ptr_map and have the functor object be given the *value* of each item iterated instead of a key/value pair like it does with std::map? Help is appreciated, thank you.

4 6

serialization problems (undefined reference - boost::archive::detail::archive_pointer_oserializer<...>)
by Allan Johns 16 Sep '08

16 Sep '08

Hi, I've written my own archive, which works fine until I try serialising a boost::shared_ptr<X>, in which case I get: undefined reference to `boost::archive::detail::archive_pointer_oserializer<boost::archive::boost_oarchive>::~archive_pointer_oserializer(). (boost::archive::boost_oarchive is my archive class, in case this causes confusion). I'm on gcc4.1.2, ceontos4 x86_64. I'm linking to libboost_serialization-gcc41-mt-1_35.so also. I've hit a bit of a brick wall here so any help would be greatly appreciated. I've searched around but can't seem to find any relevant posts on this subject. cheers A _________________________________________________________________ Get all your favourite content with the slick new MSN Toolbar - FREE http://clk.atdmt.com/UKM/go/111354027/direct/01/

3 5

Error while using asio and xpressive together
by Rohit Sauhta 16 Sep '08

16 Sep '08

I get compiler error with the following code: #include <boost/asio.hpp> #include <boost/xpressive/xpressive.hpp> int main(int argc, char*argv[]) {} If I flip the order of #include, code compiles fine. I am using gcc 4.1.2 compiler on linux. Does this need to be fixed in asio ? thx Rohit

2 1

Problem with date_time facets
by Tavares, Pedro (London) 16 Sep '08

16 Sep '08

Hi all, I'm using boost with stlport 5.1.5 in msvc 7.1. when I try to use date facets, the compiler complains there is not suitable std::locale ctor, although I can see it in the code and all flags seem to be defined correctly (_STLP_MEMBER_TEMPLATES is defined). I'm trying to compile the following excerpt: 1 std::stringstream str(__DATE__); // for example "Sep 16 2008" 2 3 boost::gregorian::date_input_facet facet("%b %d %Y"); 4 std::locale loc(str.getloc(),facet); 5 str.imbue(loc); 6 7 boost::gregorian::date d; 8 str >> d; The error is in line 4 and the message is that the (templated) ctor does not exist. Thanks for your assistance, Pedro -------------------------------------------------------- This message w/attachments (message) may be privileged, confidential or proprietary, and if you are not an intended recipient, please notify the sender, do not use or share it and delete it. Unless specifically indicated, this message is not an offer to sell or a solicitation of any investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Merrill Lynch. Subject to applicable law, Merrill Lynch may monitor, review and retain e-communications (EC) traveling through its networks/systems. The laws of the country of each sender/recipient may impact the handling of EC, and EC may be archived, supervised and produced in countries other than the country in which you are located. This message cannot be guaranteed to be secure or error-free. This message is subject to terms available at the following link: http://www.ml.com/e-communications_terms/. By messaging with Merrill Lynch you consent to the foregoing. --------------------------------------------------------

1 0

date-time library and checked iterators
by gast128 16 Sep '08

16 Sep '08

Dear all, last week we switched to vstudio 2008. It has checked iterator support and it already catched two incorrect (but probably also harmless) uses of iterators. Maybe in the date time library there is also such a case. The stream operator on ptime eventually calls date_time::date_facet::do_put_tm () function which probably uses an incorrect way of dereferencing string iterators when empty: // use time_put facet to create final string return std::use_facet<std::time_put<CharT> >(a_ios.getloc()).put(next, a_ios, fill_char, &tm_value, &*a_format.begin(), &*a_format.begin()+a_format.size()); When a_format is empty the begin iterator may not be dereferenced? I do know that the actual code is harmless, but now we get the M$ checked iterator error message, and turning it globally off would be pity, since it cna be an extra potential debugging tool. Wkr, me

1 0

[test] Passing parameters to fixtures
by Markus Schöpflin 16 Sep '08

16 Sep '08

Hello, to set up and tear down database connections for unit tests, I need something like parametrized test fixtures. Up to now (using an old version of Boost.Test) I was creating a customized test suite (by deriving from test_suite) and performed the connection handling during construction/destruction of the customized test suite. As the latest Boost.Test now has explicit support for test fixtures, I was looking at how I could replace my old approach by using a test suite fixture. The fixture would need to look something like this: struct F { F(string db_name) { connect to db_name } ~F() { disconnect from db_name } }; Now, the Boost.Test documentation tells me that a fixture is supposed to be used like this: BOOST_FIXTURE_TEST_SUITE( s, F ) So there doesn't seem to be a way of passing parameters to the constructor of the fixture. Is there any? Or is there any other way to obtain a parametrized fixture? Or should I just keep on using customized test suites? TIA, Markus

4 10

Whatever happened to singleton class?
by Kurt Kohler 15 Sep '08

15 Sep '08

Back in January, the review of Tobias Schwinger's singleton package resulted in it being rejected. At the time it was stated that a new version would be out for review in three months or so. Has anything happened since then? I've been using the class without problems for some time, but I'd feel more comfortable if it was an official part of boost.

2 1

boost.extensions and boost.reflection.
by Germán Diago 15 Sep '08

15 Sep '08

Hello. I'm implementing a property class which uses my own library (still in early stages) and I want to extend it to general reflection (not for now) and shared library loading. I found boost.extensions, which is not a boost library for now. I don't know if this is the place to ask for this, if it is not, point me where I could go. It's great to see I won't have to taje any more pain to load plugins :-). I would like to make a feature request. In boost.extensions, factories are used to construct types of a derived class with pointers. So, in order to register a new class, you have to tell which is the base class to the extensions system. I think there is a better way, with which you wouldn't need to do this. It is inspired in this type style of value-based type system: http://stlab.adobe.com/wiki/index.php/Image:2008_06_26_classes_that_work.pdf An object which can contain any other object (like boost::any) could be created. This way (this is how I do in my own solution) you just have to register a type without worrying about its base class: REGISTER_CLASS(myns, myclass) Now I can do like this: object_t myobject = introspection::create_object("myns", "myclass"); when I want my object to become "myclass" I do: myns::myclass & refclass = get_reference<myns::myclass>(myobject); This works fairly well, and factories go away, freeing the user from learning more interfaces. Just register your type and use it. Everything else is transparent. The interface is simple, no factories or anything else to handle. This can be also used from shared libraries without problems. At least, I think that it should be provided a way to register a factory of non-pointer types. In the documentation it says a pointer is created for the animal class, disabling this type of value-based registration.

2 4

fusion::result_of::transform<Seq1,Seq2,F>
by e r 15 Sep '08

15 Sep '08

hello, here's what I'm trying to do: *.cpp //result_type() not valid typedef fusion::vector<A,B,C> result_type; //arg2s_type() is valid typedef fusion::vector<Arg2A,Arg2B,Arg2C> arg2s_type; //transforms // (fusion::vector<identity<A>,identity<B>,identity<C> >(),arg2s_type()) // into {A(arg1,Arg2A()),B(arg1,Arg2B()),C(arg1,Arg2C()))} result_type result( range<result_type,args2_type>::create( arg1 //arbitrary type Arg1 ) ); here's my attempt. problems/questions are shown in comments. *.hpp: template<template<typename> class metafun = mpl::identity> struct apply_wrapper{ template<typename T> struct apply{ typedef metafun<T> type; }; }; template<typename Seq,template<typename> class metafun = mpl::identity> struct apply_wrapper_to_seq{ typedef typename mpl::transform< Seq, // e.g. fusion::vector<A,B,C> apply_wrapper<metafun> >::type type; //e.g. fusion::vector<identity<A>,identity<B>,identity<C> > }; template<typename Arg1> struct fun{ fun(const Arg1& args):args_(args_){} //copy, assign... // probably not what result_of::transform expects, based on compile // errors (below) template<typename Metafun,typename Arg2> struct result{ typedef typename Metafun::type type; }; template<typename Metafun,typename Arg2> typename Metafun::type //e.g Metafun = identity<A> operator()(const Metafun& meta,const Arg2& arg2)const{ typedef typename Metafun::type result_type; //e.g. A return result_type(args,arg2); } const Arg1& args_; }; template<typename Result,typename Arg2s> struct range{ //e.g. fusion<identity<A>,identity<B>,identity<C> > typedef typename apply_wrapper_to_seq<Result>::type wrappers_type; //e.g. fusion::vector<Arg2A,Arg2B,Arg2C> typedef Arg2s arg2s_type; template<typename Arg1> struct result{ typedef typename fusion::result_of::transform< wrappers_type, arg2s_type, fun<Arg1> >::type type; }; template<typename Arg1> static typename result<Arg1>::type create(const Arg1& args){ typedef fun<Arg1> f_type; wrappers_type wrappers; arg2s_type arg2s; f_type f(args); BOOST_MPL_ASSERT( ( mpl::equal< Result, typename result<Arg1>::type > ) );//result_of::fun causes compile error /usr/local/boost_1_35_0/boost/utility/result_of.hpp|34|instantiated from ‘boost::detail::result_of_impl< factory::fun<Arg1>, factory::fun<Arg1> > ()(boost::mpl::identity<A>, Arg2A), false>’| ... //usr/local/boost_1_35_0/boost/utility/result_of.hpp|68|error: wrong number of template arguments (1, should be 2)| //factory/range.hpp|32|error: provided for ‘template<class Arg1> template<class Metafun, class Arg2> struct factory::fun<Arg1>::result’| //usr/local/boost_1_35_0/boost/fusion/view/transform_view/detail/value_of_impl.hpp|55|error: no type named ‘type’ in ‘struct //boost::mpl::apply<boost::fusion::detail::apply_transform_result<factory::fun<Arg1>, boost::mpl::identity<A>, Arg2A, mpl_::na, mpl_::na, mpl_::na>’| return fusion::transform( wrappers, arg2s, f ); } }; any help would appreciated. thanks!

2 7

boost.extensions bugs?
by Germán Diago 15 Sep '08

15 Sep '08

Hello. I downloaded boost.extensions from http://boost-extension.blogspot.com/?gclid=CNjp5dfJ2JUCFQsZQgod0mHbWg When I tried the first example (the shared_library one) in the tutorial, I realized that the macro BOOST_EXTENSION_EXPORT_DECL didn't prevent c++ name mangling for the example function. I had to add extern "C" before void manually. And in the second tutorial (the animals tutorial) BOOST_EXTENSION_TYPE_MAP_FUNCTION seems to be called, but when I get the map from main, it is empty. The library is found (LD_LIBRARY_PATH is set so that it finds the library) but it does not work. Thank you. Tested in gcc 4.2.3 under ubuntu 8.04.

2 3

Memory/CPU usage
by Jean-Sebastien Stoezel 15 Sep '08

15 Sep '08

Hi, Is there a library in Boost that provides memory/CPU usage estimates? Thanks, Jean

2 1

question about boost::thread
by PingShan Li 15 Sep '08

15 Sep '08

Here is my test program using boost::thread. I would expect this program to crash inside FunctionA because m_ClassA is no longer available. Can anybody help me to understand why it does not crash? thank you. [root@localhost]# uname -a Linux localhost.localdomain 2.6.9-22.EL #1 Mon Sep 19 18:20:28 EDT 2005 i686 i686 i386 GNU/Linux [root@localhost]# g++ --version g++ (GCC) 3.4.4 20050721 (Red Hat 3.4.4-2) Copyright (C) 2004 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. g++ -I/opt/third_party_libraries/boost_1_33_1 -L/opt/third_party_libraries/boost_1_33_1/stage/lib -lboost_thread-gcc-mt main.cpp -o test #include <boost/bind.hpp> #include <boost/thread.hpp> #include <iostream> void SleepTime( int a ) { boost::xtime xt; boost::xtime_get( &xt, boost::TIME_UTC ); xt.sec += a; boost::thread::sleep( xt ); } class ClassA { public: ClassA( int member ) : m_member( member ) { std::cout << "ClassA constructor: " << m_member << std::endl; } virtual ~ClassA( ) { std::cout << "ClassA destructor: " << m_member << std::endl; } void SetMember( int a ) { m_member = a; } int GetMember() const { return m_member; } private: int m_member; }; class TestClass { public: TestClass( ) : m_ClassA( 0 ) { std::cout << "TestClass constructor: " << m_ClassA.GetMember() << std::endl; } virtual ~TestClass( ) { std::cout << "TestClass destructor: " << m_ClassA.GetMember() << std::endl; } void RunThreadFunction() { std::cout << "RunThreadFunction start" << std::endl; boost::thread thr( boost::bind( &TestClass::ThreadFunction, this ) ); std::cout << "RunThreadFunction end" << std::endl; } void ThreadFunction( ) { std::cout << "ThreadFunction start" << std::endl; m_ClassA.SetMember( 5 ); SleepTime( 5 ); FunctionA( ); return; } void FunctionA( ) { std::cout << "Inside FunctionA: " << m_ClassA.GetMember() << std::endl; } private: ClassA m_ClassA; }; int main() { { TestClass a; a.RunThreadFunction(); } std::cout << "main wait" << std::endl; SleepTime( 10 ); return 0; }

3 3

[review] FSM Library review result
by Martin Vuille 15 Sep '08

15 Sep '08

This is a summary of the comments received during the review of Andrey Semashev's Finite State Machines (FSM) library. Apologies for the delay in getting these out. DOCUMENTATION * Relocate ToC to make it stand out. * Several people used the Wikipedia article http://en.wikipedia.org/wiki/Finite_state_machine as a reference for FSM terminology and operation, and found discrepancies between Boost.FSM and that description. Perhaps Boost.FSM should explicitly describe its FSM metamodel, or refer to an existing metamodel (Wikipedia FSM or Harel or UML Statechart, for example). The latter was mentioned several times as being preferred since it is a standard. * If possible, use standard terminology. For example, "transition map" vs. "state transition table". Or define the non-standard terms. * Include a comprehensive rationale mapping the design choices to the design objectives. * Compare/contrast Boost.FSM with the FSM implementation as described in "C++ Template Metaprogramming". * Add an example of event deferral using boost::function. * Clarify support for multithreading vs. asynchronous FSM, as some were confused by existing text. * Clarify lifetime of objects. * Add implementation of example using transition map/STT. * Add more complex example(s). SCOPE/FEATURES These were features that were suggested or asked about. Some or all may not be suited for addition to the library. In that event, it may be useful to explicitly mention in the documentation that they are not supported, and why. * Support nested states. Return-to-history was cited as an example of a benefit of nested states over nested FSM. * In STT, support matching "any" from state. * Add syntactic sugar to support "synthetic" states (cf. http://lists.boost.org/Archives/boost/2008/08/140714.php) * Support event deferral. * Support data-dependent transitions (perhaps this is the same as the synthetic state suggestion above). * Improve modeling of the "transition" concept. Specifically, there was an issue with the fact that the action was associated with a state rather than a transition. INTERFACE * There was a lot of discussion comparing the amount of code required to implement an "ad hoc" FSM, vs. the amount of code required to implement the same FSM using Boost.FSM. * The "transition map" representation was deemed to contain too much syntactic noise and not sufficiently similar to a traditional STT, and it was suggested that it should include the transition action. * Some felt that the interface was too procedural rather than being declarative. IMPLEMENTATION * There was quite a bit of discussion of the Boost.FSM implementation vs. the C++TM implementation, but I don't believe there were any specific conclusions reached. * Handling of event is different depending on whether or not transition map is used (handled by "to" state vs. current state, respectively). This is also the case when an event is not found in the transition map. This could lead to errors. Thanks again to Andrey for his submission and to all the reviewers and other who made comments for their input. MV

1 0

[serialization] broken in 1.36
by gast128 15 Sep '08

15 Sep '08

Dear all, yesterday we upgraded to vstudio 2008 and Boost 1.36. However it seems that the serialization library gives a STATIC_WARNING now. the code uses a shared_ptr of a data structure which has no virtual function. This was ok in Boost 1.34 and I don't see why this should be wrong: #include "stdafx.h" #include <sstream> #include <boost\shared_ptr.hpp> #include <boost\serialization\shared_ptr.hpp> #include <boost\serialization\nvp.hpp> #include <boost\archive\xml_iarchive.hpp> struct Data { std::string m_str; }; template <class Archive> void serialize(Archive& ar, Data& r, const unsigned int /*version*/) { ar & BOOST_SERIALIZATION_NVP(r.m_str); } struct DataStorage { template <class Archive> void serialize(Archive& ar, const unsigned int /*version*/) { ar & BOOST_SERIALIZATION_NVP(m_ptrBla); } private: //data typedef boost::shared_ptr<Data> DataPtr; DataPtr m_ptrBla; }; int _tmain() { DataStorage data; std::stringstream sstr; //boost::archive::xml_oarchive oa(sstr); //oa << boost::serialization::make_nvp("bla", data); boost::archive::xml_iarchive ia(sstr); ia >> boost::serialization::make_nvp("bla", data); return 0; } It gives warning c4099 where '<---': const extended_type_info * get_derived_extended_type_info(const T & t) const { // note: this implementation - based on usage of typeid (rtti) // only does something if the class has at least one virtual function. BOOST_STATIC_WARNING(boost::is_polymorphic<T>::value); //<--- return detail::extended_type_info_typeid_0::get_extended_type_info( typeid(t) );

4 4

[shared_ptr] why isn't null_deleter included into smart_ptr lib
by Ovanes Markarian 15 Sep '08

15 Sep '08

Hi all! I am wondering, why null_deleter which is sugested in the programming techniques web site of shared_ptr library not a part of utility lib or smart_ptr lib. In the past I worked in at least 3 projects where people defined there own null_deleter. Best Regards, Ovanes

1 0

Problems with boost::asio::local::stream_protocol::iostream under Boost 1.36.0
by Jason Bertschi 15 Sep '08

15 Sep '08

I'm trying to use asio::local::stream_protocol::iostream to connect to a server (using Boost library version 1.36.0). The code looks something like this: boost::asio::local::stream_protocol::iostream mgmtStream("/tmp/pipes/mgmtsock"); if (!mgmtStream) throw std::exception(); // Send cmd to mgmt mgmtStream << cmd << std::flush; I get a compilation error on the line creating mgmtStream. The interesting part is this: no type named 'resolver_query' in 'class boost::asio::local::stream_protocol' I tried breaking the creation into two steps (create local::stream_protocol::endpoint with the name of the socket then passing the endpoint into the iostream constructor), but the result was about the same (the failure occurred on the line creating the iostream, not the line creating the endpoint). The problem seems to be that basic_socket_streambuf<stream_protocol> requires the definition of type resolver_query (within stream_protocol in this case). It seems that ip::tcp::iostream declares it to be of type ip::basic_resolver_query<tcp>; I saw no obvious equivalent in the local namespace, and my attempt to add 'typedef ip::basic_resolver_query<stream_protocol> resolver_query;' to stream_protocol of course did nothing helpful (just added a lot more compilation errors). Frankly, I'm not sure how stream_protocol::iostream could possibly compile without this definition somewhere... Any ideas? Below is the full output from g++ (in case there's something helpful): export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp: In instantiation of 'boost::asio::basic_socket_streambuf<boost::asio::local::stream_protocol, boost::asio::stream_socket_service<boost::asio::local::stream_protocol> >': export_Darwin_i386/include/boost/utility/base_from_member.hpp:69: instantiated from 'boost::base_from_member<boost::asio::basic_socket_streambuf<boost::asio::local::stream_protocol, boost::asio::stream_socket_service<boost::asio::local::stream_protocol> >, 0>' export_Darwin_i386/include/boost/asio/basic_socket_iostream.hpp:86: instantiated from 'boost::asio::basic_socket_iostream<boost::asio::local::stream_protocol, boost::asio::stream_socket_service<boost::asio::local::stream_protocol> >' build_Darwin_i386/confdb/ObjectManager.cc:461: instantiated from here export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp:252: error: no type named 'resolver_query' in 'class boost::asio::local::stream_protocol' export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp: In member function 'boost::asio::basic_socket_streambuf<Protocol, StreamSocketService>* boost::asio::basic_socket_streambuf<Protocol, StreamSocketService>::connect(T0) [with T0 = const char*, Protocol = boost::asio::local::stream_protocol, StreamSocketService = boost::asio::stream_socket_service<boost::asio::local::stream_protocol>]': export_Darwin_i386/include/boost/asio/basic_socket_iostream.hpp:106: instantiated from 'boost::asio::basic_socket_iostream<Protocol, StreamSocketService>::basic_socket_iostream(T0) [with T0 = const char*, Protocol = boost::asio::local::stream_protocol, StreamSocketService = boost::asio::stream_socket_service<boost::asio::local::stream_protocol>]' build_Darwin_i386/confdb/ObjectManager.cc:461: instantiated from here export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp:131: error: no type named 'resolver_query' in 'class boost::asio::local::stream_protocol' export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp:131: error: no type named 'resolver_query' in 'class boost::asio::local::stream_protocol' export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp:131: error: no type named 'resolver_query' in 'class boost::asio::local::stream_protocol' export_Darwin_i386/include/boost/asio/basic_socket_streambuf.hpp:131: error: 'resolve_and_connect' was not declared in this scope Thanks, Jason Bertschi jbertschi(a)mac.com

2 2

[multi_index_container] Usage Idioms
by Robert Jones 15 Sep '08

15 Sep '08

My head is now exploding with understanding the full power and flexibility of multi-index-container, but still it is not clear to me how best to do the simple things! What is the idiomatically 'correct' way to apply the equivalent functionality of the erase-remove idiom to a multi-index-container? I'm assuming that this, (very much abridged for brevity of exposition) multi_index_container mic; mic.erase( remove_if( mic.begin(), mic.end(), pred ), mic.end() ); is doomed since the remove algorithms overwrite removed elements with copied elements which would cause havoc with other indices, and in any case this kind of modification through iterators is explicitly prohibited. I did think of extracting a vector of references, doing erase-remove on that and then applying rearrange(), but it seems rather inelegant. Is there a better way? Thanks. - Rob.

3 4

Documentation about design and implementation
by Kartik Mahajan 15 Sep '08

15 Sep '08

Hi I have recently installed Boost 1.36. I am right now experimenting with the Boost.thread library primarily for the purpose of learning and I am trying to use them in the project I am working. I also wish to learn to use asio and interprocess libraries in near future. I have gone through the documentation about how to use the thread library, but I guess there is nothing mentioned about its design and implementation. The only reason I am interested in some documentation related to its design and implementation is purely for learning purpose. As Boost libraries are designed mostly by experts, I would like to broaden my horizons "on how to design". I would not like to be just a user of such expertly designed libraries and would like to learn the ins of designing. Also going through the code would I guess improve my skills. I did read some include files and also installed cscope on my linux box so that I can go through code easily but its too hard for me to comprehend why the things ie code is written the way it is. Is some documentation related to implementation of the library available ? I guess no ? Do we just have to comprehend by reading the code ? Are there some tips for reading the code ( I am even unable to find which file to start from, I am still a newbie ) I just need some tips and guidance. Thanks & Regards Kartik Mahajan

3 2

IoStreams: Weird bzip2 behavior?
by Dr. Roland Bock 15 Sep '08

15 Sep '08

Hi, when experimenting with IoStreams a bit, I tried bzip2 compression, too. In contrast to zlib and gzip compression, it did not work as expected. I have a bit weird behavior in two aspects. a) Unknown error code: ====================== The attached code yields: Caught bzip2 error with code: -2 data_error: -4 data_error_magic: -5 config_error: -9 So for some reason, I am catching a bzip2_error with an error code which is not even documented. When I replace gzip2 by zlib, it works fine. b) Empty output of compression: =============================== When I use a std::ofstream instead of the decompressingStream, I get an empty file. This might be the reason for a), but then I would have expected data_error or data_error_magic? Decompressing the content of a valid bzip2 compressed file works fine. Any ideas what might be going wrong? Thanks in advance, Roland

1 0

[Boost][Serialization] CPU bottleneck
by Vjekoslav Brajkovic 14 Sep '08

14 Sep '08

Hi, I am using the serialization library in my project and it has been functioning perfectly thus far. However, when I've scaled up the usage requirements, I had hit a very odd problem. Let me explain the use case. Serialization library is used in a DFS framework, handling large data structures (in terms of size, not complexity) such as std::vector<char> of size 1MB and above. The framework consists of two major components: Chunkserver (server) and a Client. Files are chunked, wrapped in a class, serialized and sent over the wire. Same things is done on the server side, but in a reverse order. The actual binary data is stored in a vector (previously, I've tried using string instead, but I had some issues with it and Robert suggested using some an alternative container). When I was depositing large files to Chunkserver, disk utilization was almost non-existent, whereas the CPU was maxed out. It is important to realize that this problem occurred only on the server side, not client. Upon further investigation using gprof I have concluded that the bottleneck was in the serialization library (it also may be the case that I am misusing it). According to the profiler, above 97% of the CPU time was spent in a singe function. Profiler results can be found at this address: http://www.cs.washington.edu/homes/balkan/gprof.txt For the reference, the signature of that function is: boost::serialization::serialize_adl< boost::archive::text_iarchive, std::vector...> and I am using text archive. I as mentioned before, this issue only occurs on a server side. I would appreciate if anybody could explain why this is happening and more importantly how to circumvent the issue. Thank you! Vjeko

2 2

What's the status of unordered_map.hpp?
by Peng Yu 14 Sep '08

14 Sep '08

Hi, In http://www.boost.org/doc/libs/1_35_0/doc/html/boost_tr1/unsupported.html, it shows the header file is <boost/tr1/unordered_set.hpp> for unordered_set. But I only find the following two files in version 1.36.0. boost/unordered_map.hpp I'm wondering if unordered_map is not stable yet, so that I'd better avoid using it. Or it will be stable from version 1.36.0 on? Thanks, Peng

2 1

Missing MSVCR80.DLL
by Slava D 13 Sep '08

13 Sep '08

guys, please, could you help me. I have installed boost_1_35 with the BoostInstaller (taking the precompiled binaries). When I check any dll-s with the dependency walker (say, release version BOOST_DATE_TIME-VC-MT-1_35.dll or debug version BOOST_DATE_TIME-VC-MT-GD-1_35.dll), it says that it is missing MSVCR80.dll for the release version and MSVCR80D.DLL for the debug version. At the beginning I thought there was something wrong with my PC. I tried on another machine and got the same results. On one machine I have XP with SP2 and on another I have XP with SP3. Some people are saying that this usually shows some mess with the manifest files. But I did not need to generate the manifest file as I took the binaries from the Installer directly. Please, could you help me. Any advice would be greatly appreciated. many thanks, Slava

2 1

Serialization: storing different representations in different archive types
by Simon Fraser 13 Sep '08

13 Sep '08

I have a program that saves program state in both binary and XML archives. I'd like to store one of the model objects in my program in different formats, depending on whether the output archive is XML or binary: for XML archives, I'd like to use a human readable-format, and for binary archives I'd like to use a much more compact representation. I don't see any methods on Archive that let me ask if the output is a textual format (text or XML). I could dynamic_cast in my load/save methods, but that doesn't extend to new kinds of archives that may be implemented in future. Is there a way to do what I want to do? Thanks Simon

2 1

enabled_shared_from_this: bad_weak_ptr exception + online doc explanation
by cxv＠sfu.ca 13 Sep '08

13 Sep '08

Hi all, I have a class called TextTool. In its constructor I initialize a member variable. This member variable needs a pointer to TextTool in *its*constructor. Hence I need to have a pointer to "this" (TextTool) and then pass it to the constructor of the member variable. This is a summery of my code: *TextTool.h* class TextTool : public Tool, public boost::enable_shared_from_this<TextTool> { public: TextTool(QDialog *taskDialogue); private: boost::shared_ptr<ToggleControl> bold; //Member variable that needs a pointer to TextTool in its constructor }; *TextTool.cpp* TextTool::TextTool(QDialog *taskDialogue) : Tool(this->name) { boost::shared_ptr<TextTool> pointerToThis = TextTool::shared_from_this(); //ERROR OCCURS ON THIS LINE bold = boost::shared_ptr<ToggleControl>(new ToggleControl(pointerToThis)); } I get a runtime exception: "boost::bad_weak_ptr at memory location 0x0012fccc" when executing the above mentioned line. On the BOOST online documentation, I dont understand what this line means: "**this* must be a subobject of an instance *t* of type *T* . There must exist at least one *shared_ptr* instance *p* that *owns* *t*.". Do I need to have an instance (t) of TextTool (T) as a member variable of the class TextTool? Won't this lead to loops in my situation (since I want the "this" pointer to be created in the constructor itself)? Any help? Thanks, /C.

3 4

jam environment variables
by Mika Heiskanen 13 Sep '08

13 Sep '08

Hello, Jam documentation mentions that "Jam picks up variable settings from your environment by default". However, I could not find any documentation on what environment variables affect what options. In particular, I am looking for a way to pass on to Jam the --layout and --build-type options via environment variables. Currently I am building a boost rpm for local distribution by using the following command sequence in the rpm .spec file: %build ./configure --prefix=%{_prefix} --libdir=%{_libdir} cat Makefile | sed -e 's/BJAM_CONFIG=/BJAM_CONFIG=--layout=system --build-type=complete/' > Makefile.new mv Makefile.new Makefile make all If I understand correctly, I should be able to define the compile options via environment variables instead of resorting to a hack like above. I'd appreciate any pointers to more detailed documentation on how to accomplish the above with environment variables alone. Thank you in advance, --> Mika Heiskanen / FMI

2 1

what is a vertex_descriptor? (boost graph library)
by Will Chen 13 Sep '08

13 Sep '08

So it looks like it's basically a 0-based integer. When I start adding vertices to an empty graph, the first one comes back as 0, the second as 1, third as 2...etc. Is it always an integer? When is it not an integer? I really want a way to easily convert vertex_descriptor's and edge_descriptor's to and from strings. Any ideas? -- William Yun Chen '09 Hinman Box 1826 Dartmouth College Hanover, NH, 03755

2 1

retrieve the path of an opened mapped_file!
by Michael Bradley Jr 13 Sep '08

13 Sep '08

Hi, looking for an interface to access the path of an opened boost::iostreams::mapped_file file or its mapped_file_params parameter ? Any hint ? thx in advance Mike

1 0

Boost.tokenizer and char_separator
by Sean Farrow 13 Sep '08

13 Sep '08

Hi: I am in the process of using boost::tokenizer in a bimap. I have the following definition: boost::bimaps::bimap<boost::bimaps::set_of<boost::tokenizer<boost::char_ separator<char>>>, std::string> TokensList; I need to use the " " as the separator. How can I do this? Any help apreciated. Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3439 (20080912) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

1 0

boost serialization and datatype mismatch
by sam p 12 Sep '08

12 Sep '08

Hi, How to validate datatype before it gets deserialized? e.g. struct Abc { std::map<string,string> tmpMap; int a; float d; std::list<string> stringList; void serialize(boost::archive::polymorphic_oarchive & ar, const unsigned int file_version) { ar & tmpMap; ar & a; ar & d; ar & stringList; } void serialize(boost::archive::polymorphic_iarchive & ar, const unsigned int file_version) { ///////////////////////////////////////////////////////////////////// /* Now the right thing to do over here is ar & tmpMap; ar & a; ar & d; ar & stringList; */ /////////////////////////////////////////////////////////////////////// //But instead, if by mistake user writes something like ar & a; ar & d; ar & stringList; ar & tmpMap; /* So how to handle such problem? Can I validate data somehow before it gets deserialized? On some platforms like SuSE linux I have observed that such thing doesn't throw exception and we get SEGV. */ } }; Thanks, Sameer

3 3

[serialization] missing </serialization> tag
by Mojmir Svoboda 12 Sep '08

12 Sep '08

afternoon, i am serializing graph::adjacency_list via boost::serialization but there is no tag </serialization> at the end of the generated file. what am i doing wrong, please? i suspect also there may be bug in binary serialization in 1.36.0 because i cannot read generated file. i'll try to isolate this in nearest future. best regards, mojmir

2 1

Puzzled: compiler can't find a match for function call
by Zeljko Vrba 12 Sep '08

12 Sep '08

In the code below, the compiler complains with q.cc:39: error: no matching function for call to `inc2(boost::fusion::map<boost: :fusion::pair<detail::KEY, int>, boost::fusion::void_, boost::fusion::void_, boo st::fusion::void_, boost::fusion::void_, boost::fusion::void_, boost::fusion::vo id_, boost::fusion::void_, boost::fusion::void_, boost::fusion::void_>&)' id_t<K> is the SAME type as the expanded BF::map type in inc1; it even works as the return type of inc1, yet I can't use it as an argument to inc2. What am I missing? This happens both on gcc 3.4 and SunCC 12. #include <boost/fusion/include/at_key.hpp> #include <boost/fusion/include/comparison.hpp> #include <boost/fusion/include/erase_key.hpp> #include <boost/fusion/include/io.hpp> #include <boost/fusion/include/joint_view.hpp> #include <boost/fusion/include/map.hpp> #include <boost/fusion/sequence/intrinsic/at_key.hpp> #include <boost/fusion/sequence/intrinsic/value_at_key.hpp> namespace detail { namespace BF = boost::fusion; struct KEY; template<typename K> struct id_t { typedef BF::map<BF::pair<K, int> > type; }; template<typename K> inline typename id_t<K>::type& inc1(BF::map<BF::pair<K, int> > &id) { ++BF::at_key<K>(id); return id; } template<typename K> inline typename id_t<K>::type& inc2(typename id_t<K>::type &id) { ++BF::at_key<K>(id); return id; } void f() { BF::map<BF::pair<KEY, int> > m(12); inc1(m); inc2(m); } }

4 5

Boost.tokenizer, splitting at a space only boundary
by Sean Farrow 12 Sep '08

12 Sep '08

Hi: Is the a function provided with boost.tokenizer to split at a space only boundary, rather than space and punctuation? Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3436 (20080911) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

2 1

Is there a false-position root finding method in boost
by Peng Yu 12 Sep '08

12 Sep '08

Hi, #include <boost/math/tools/roots.hpp> There are a few root finding algorithm in the above file. I'm not sure if there is the false-position method in there? What I want is give an interval which only has one root. I want to always find the root in that interval. I'm wondering if any function in that header can do so or not. Thanks, Peng

3 3

wrap native C++ DLL used Boost libs, into .NET
by aidforsoft＠mail.ru 12 Sep '08

12 Sep '08

Hello! I need to use a DLL used Boost, in .NET projects. I wrapped this lib, but I cannot use the wrapping, because System.BadImageFormatException (is not a valid Win32 application. (Exception from HRESULT: 0x800700C1)) raises at once, if I executing an application using the wrap. Wrap scheme: Native DLL --- .NET Class Library --- .NET Project. I'm wrapping every class in native DLL into .NET class. I using some principles from the "Expert C++/CLI: .NET for Visual C++ Programmers" by Marcus Heege. When I wrote a small test project, I discovered that if I only include anyone Boost header into native DLL, it set the System.BadImageFormatException permanently. Without Boost wrapping works perfectly. I use: Boost 1.35.0 Visual Stidio 2005 SP1, 2008 - same results in all cases. Windows XP SP2 x86. I found same problems in Internet - impossible to wrap native DLLs, used Boost. All this problems were unsolved. Such as: http://objectmix.com/dotnet/121318-not-valid-win32-application-exception-hr… -- Best regards, Ilya Chumakov mailto:aidforsoft@mail.ru

7 8

[Asio] Multiple Servers using io_service
by Dominik Steenken 12 Sep '08

12 Sep '08

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello everyone, i am trying to create a program where two servers accept incoming tcp connections, each at a different port. I worked through the tutorials and the used async_accept as described there to listen for connections. For a single server that worked fine. For the second server i postponed calling io_service.run() until both async_accept operations were executed. Both Instances use the same io_service. But now neither port is opened when i start the program. No exceptions, nothing. I realize that i am new to using boost and that this may be a stupid question, but still, it is a puzzling error to me and time is somewhat of the essence here, so if you could please give me a hint on how to proceed, i would greatly appreciate it. Thanks in advance, Dominik Steenken -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFIyYVKaIgTXFmz1t0RAgzKAJ9gvNcQl5+TVuiQJv8qQA+cGubeTgCeMEQo yZV1pq14n481VkdomJUgwAE= =UpHz -----END PGP SIGNATURE-----

2 1

Static linkage in shared object
by Graham Bull 12 Sep '08

12 Sep '08

Hi all, Using Linux and g++, is it possible to create a shared object that statically links to Boost.Thread (1.33.1)? I'm doing something like: g++ -static -pthread -lboost_thread-gcc-mt -shared -o <name>.so <sourcefiles> to create a shared object (it's a JNI library written in C++). It compiles fine, but when I use it from Java I always getting an exception stating that libboost_thread-gcc-mt-1_33_1.so.1.33.1 cannot be found - but that's intentional, I haven't put /usr/local/lib in LD_LIBRARY_PATH because I don't want to dynamically link. Any help greatly appreciated!

3 2

Re: [Boost-users] Puzzled: compiler can't find a match for function call
by JOAQUIN M. LOPEZ MUÑOZ 11 Sep '08

11 Sep '08

________________________________________ De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de Zeljko Vrba [zvrba(a)ifi.uio.no] Enviado el: jueves, 11 de septiembre de 2008 17:05 Para: boost-users(a)lists.boost.org Asunto: Re: [Boost-users] Puzzled: compiler can't find a match for functioncall > Indeed it works. Could you please explain why the compiler can deduce > K in BF::map<BF::pair<K, int> > , but not in typename id_t<K>::type? Suppose that id_t<K1>::type == id_t<K2>::type == int (for instance). If we pass int, how can the compiler figure out whether it's K1 or K2 that has to be deduced? Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

3 2

boost::regex linking errors
by rsennat 11 Sep '08

11 Sep '08

hi all, im using boost::regex for the first time. #include <boost/regex.hpp> string aliasCmd = "xyz * abc"; boost::regex regExp("[*]", boost::regex::basic); aliasCmd = boost::regex_replace(aliasCmd, regExp, "INST"); There were no compiler errors. But during linking, I get the errors as below. Could anyone please get me on this. Thanks rsennat ../../../lib/FREEBSD_6_i686/libobj.a(IObject.o): In function `basic_regex': /sviews/ag_cli_tools//fw-boost/boost/regex/v4/basic_regex.hpp:340: undefined ref erence to `boost::reg_expression<char, boost::regex_traits<char>, std::allocator <char> >::reg_expression(char const*, unsigned int, std::allocator<char> const&) ' ../../../lib/FREEBSD_6_i686/libobj.a(IObject.o): In function `~basic_regex': /sviews/ag_cli_tools//fw-boost/boost/regex/v4/basic_regex.hpp:347: undefined ref erence to `boost::reg_expression<char, boost::regex_traits<char>, std::allocator <char> >::~reg_expression()' /sviews/ag_cli_tools//fw-boost/boost/regex/v4/basic_regex.hpp:347: undefined ref erence to `boost::reg_expression<char, boost::regex_traits<char>, std::allocator <char> >::~reg_expression()' ../../../lib/FREEBSD_6_i686/libobj.a(IObject.o): In function `boost::re_detail::perl_matcher<__gnu_cxx::__normal_iterator<char const*, std:: basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::alloca tor<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string <char, std::char_traits<char>, std::allocator<char> > > > >, boost::regex_traits <char>, std::allocator<char> >::unwind_extra_block(bool)': /sviews/ag_cli_tools//fw-boost/boost/regex/v4/perl_matcher_non_recursive.hpp:904 : undefined reference to `boost::re_detail::put_mem_block(void*)' -- View this message in context: http://www.nabble.com/boost%3A%3Aregex-linking-errors-tp19438899p19438899.h… Sent from the Boost - Users mailing list archive at Nabble.com.

1 1

Re: [Boost-users] Borland c++ 5.8.2 and Boost 1.3.6 - Thread problem???
by Stephen Kierzewski 11 Sep '08

11 Sep '08

Hello, With some further troubleshooting, I can now see the issue seems to be an access violation in cc3270MT.dll. Below are the stack trace and the actual Windows error message. It looks like Boost is actually working fine, but when the thread is created, cc3270MT.dll raises an exception. :7c812aeb kernel32.RaiseException + 0x52 :32758966 CC3270MT.___raiseDebuggerException + 0x1a :32758a40 CC3270MT.___raiseDebuggerException + 0xf4 :7c9032a8 ntdll.RtlConvertUlongToLargeInteger + 0x6a :7c90327a ntdll.RtlConvertUlongToLargeInteger + 0x3c :7c90e46a ntdll.KiUserExceptionDispatcher + 0xe :32779df2 CC3270MT.__beginthreadex + 0x22 :00341a04 BOOST_THREAD-BCB-MT-1_36.@boost@thread@start_thread$qv + 0x30 :00401769 boost::thread::thread(this=:0013FF74, f=:004012E0) :004016BC main() :32778e3e ; C:\WINDOWS\system32\CC3270MT.DLL First chance exception at $7C812AEB. Exception class EAccessViolation with message 'Access Violation'. Process ThreadTest.exe (3544) Any thoughts? Thanks, Stephen ---------------------------------------------------------------- Original Post: Hello, Has anyone successfully compiled the Boost libraries with the Borland / Codegear Turbo C++ Pro, compiler version 5.8.2? I was able to build the libraries but I got a lot of errors and a simple Hello World program using boost::thread will not work. Any help on switches or tweaks I can do to get Boost to work would be appreciated. Here is the program I am compiling and the error I get when running it. I am linking to the debug version of the multi-threaded DLL (boost_thread-bcb-mt-d-1_36.dll) The sample program compiles fine but when I run it I get an assertion error and the program terminates. Any feedback is welcome. Thank you, Stephen ________________________________ Assertion failed: p_ != 0, file .\boost/intrusive_ptr.hpp, line 149 Abnormal program termination ________________________________ #include <boost/thread/thread.hpp> #include <iostream> using namespace std; void hello_world() { cout << "Hello world, I'm a thread!" << endl; } int main(int argc, char* argv[]) { // start a new thread that calls the "hello_world" function boost::thread my_thread(&hello_world); // wait for the thread to finish my_thread.join(); return 0; }

1 0

accessing graph vertices by index
by Will Chen 11 Sep '08

11 Sep '08

Is this doable? Here's my graph: struct NodeProperties { map<string, string> Properties; }; struct EdgeProperties { map<string, string> Properties; }; typedef adjacency_list<vecS, vecS, directedS, NodeProperties, EdgeProperties> BipartiteGraph; So I'm using vecS for the vertexlist, so I should be able to access them by index right? -- William Yun Chen '09 Hinman Box 1826 Dartmouth College Hanover, NH, 03755

2 1

scoped_ptr initialization
by UberMongoose 11 Sep '08

11 Sep '08

Hi All, I'm new to Boost, and I've been taking a look at scoped pointers. Here's the example from the boost documentation: ---------------------------------------------------------------------- #include <boost/scoped_ptr.hpp> #include <iostream> struct Shoe { ~Shoe() { std::cout << "Buckle my shoe\n"; } }; class MyClass { boost::scoped_ptr<int> ptr; public: MyClass() : ptr(new int) { *ptr = 0; } int add_one() { return ++*ptr; } }; int main() { boost::scoped_ptr<Shoe> x(new Shoe); MyClass my_instance; std::cout << my_instance.add_one() << '\n'; std::cout << my_instance.add_one() << '\n'; } ---------------------------------------------------------------------- I notice that the creation of a new object for the scoped pointer has been done before the MyClass constructor. However you can't declare the scoped pointer as a member variable and then do something like this in a method: protected: scoped_pointer<ArbitaryObject> mPointerToObject; .... // Later mPointerToObject ( new ArbitaryObject() ); Why is that? Thanks! -- View this message in context: http://www.nabble.com/scoped_ptr-initialization-tp19431388p19431388.html Sent from the Boost - Users mailing list archive at Nabble.com.

3 4

[statechart] split different orthogonal regions over different translation units
by Manuel Jung 11 Sep '08

11 Sep '08

Hey, Im trying to split the orthogonal regions over differnent translation units, but it doesn't compile. The compiler complains that the type is incomplete, which i try to put on a different translation unit. What i do is: Forward declare the orthogonal region and define than the outermost state "Active" like this: struct StateInDifferentTransUnit; struct Active; struct Start : sc::asynchronous_state_machine< Start, Active >{ ... } struct Active : sc::state< Active, Start, mpl::list< State1, State2, StateInDifferentTransUnit > >{ ... } Is the split in different translationunits not possible with orthogonal regions or what could be my problem? Kind Regards Manuel

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[thread] working directory specific to each thread
by frederic.bron＠alcan.com 11 Sep '08

11 Sep '08

Is there a way to have the working directory specific to each thread? I have tried to change the working directory in each thread but the working directory seems to be the same in each thread, the last to be set. F. Bron 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.

2 1

Re: [Boost-users] [bind] [multi-index] Create type of pointer to overloaded erase method
by JOAQUIN M. LOPEZ MUÑOZ 11 Sep '08

11 Sep '08

________________________________________ De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de JOAQUIN M. LOPEZ MUÑOZ [joaquin(a)tid.es] Enviado el: miércoles, 10 de septiembre de 2008 20:34 Para: boost-users(a)lists.boost.org Asunto: Re: [Boost-users] [bind] [multi-index] Create type of pointer to overloaded erase method > > ________________________________________ > De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de Steven > Watanabe [watanabesj(a)gmail.com] > Enviado el: miércoles, 10 de septiembre de 2008 18:54 > Para: boost-users(a)lists.boost.org > Asunto: Re: [Boost-users] [bind] [multi-index] Create type of pointer to overloaded erase method > > > AMDG > > > > Peter Barker wrote: > > > RecordsContainer::size_type (RecordsContainer::*erase)(unsigned int) = > > > &RecordsContainer::erase; > > > > > > but it failed to compile. Visual Studio 2003 gives me the following > > > error on the above line: > > > <snip> > > > > > > > The following compiles for me with msvc 9.0 > > > > int main() { > > RecordsContainer::size_type (RecordsContainer::*erase)(unsigned int) = > > &RecordsContainer::erase; > > } > > Oddly enough, it fails with MSVC++ 8.0 (though it shouldn't since your > call_traits analysis is correct): > > error C2440: 'initializing' : cannot convert from 'overloaded-function' to > 'boost::multi_index::detail::ordered_index<KeyFromValue,Compare,SuperMeta, > TagList,Category>::size_type (__thiscall > boost::multi_index::multi_index_container<Value,IndexSpecifierList>::* )(unsigned int)' But the following works: int main() { typedef RecordsContainer::index<RecsByID>::type RecordsContainerByID; RecordsContainerByID::size_type (RecordsContainerByID::*erase)(unsigned int) = &RecordsContainerByID::erase; } even though my previous approach is IMHO still better. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[bind] [multi-index] Create type of pointer to overloaded erase method
by Peter Barker 11 Sep '08

11 Sep '08

Hello all, I have a container of the following type: struct RecsByID {}; struct RecsBySizeAndFit {}; typedef boost::multi_index_container< boost::shared_ptr<LastSizeFitRecord>, bmi::indexed_by< bmi::ordered_unique<bmi::tag<RecsByID>,bmi::const_mem_fun<RecordBase,unsigned int,&RecordBase::getRecID> >, bmi::ordered_unique<bmi::tag<RecsBySizeAndFit>,bmi::const_mem_fun<LastSizeFitRecord,const SizeAndFit&,&LastSizeFitRecord::getSizeAndFit> > > > RecordsContainer; The main thing to note above is that the first index is of type "unsigned int" - the record ID. I have a container of unsigned ints which represent the records to be deleted so naturally wanted to do a std::for_each() with a binder and passing in _1 to RecordsContainer::erase. Not that simple because Records::Container::erase has three overloads so I'm trying to come up with a type that will represent the overload I want. I've tried this: RecordsContainer::size_type (RecordsContainer::*erase)(unsigned int) = &RecordsContainer::erase; but it failed to compile. Visual Studio 2003 gives me the following error on the above line: error C2440: 'initializing' : cannot convert from 'overloaded-function' to '<Unknown>' I've decided this particular pointer to member would not be intuitive to use in production code, but I thought I'd try to get it working and failed and would like to know what I'm doing wrong! Regards, Pete

2 2

boost parameter - overloading on keyword "signature"
by e r 11 Sep '08

11 Sep '08

hello, i have something like this: *hpp : namespace tag{ template<typename Id> struct sequence{ static ::boost::parameter::keyword< a_<Id> >& a; static ::boost::parameter::keyword< b_<Id> >& b; static ::boost::parameter::keyword< arg_method_<Id> >& arg_method; }; } namespace sequence_arg{ struct method{}; struct a:public method{}; struct b:public method{}; } class sequence{ public: template<typename Id,typename ArgPack> sequence(const Id& id,const ArgPack&args){ fill_elements(id,args,args[tag::sequence<Id>::arg_method]); } private: template<typename Id,typename ArgPack> void fill_elements( const Id& id, const ArgPack& args, sequence_arg::a method ); template<typename Id,typename ArgPack> void fill_elements( const Id& id, const ArgPack& args, sequence_arg::b method ); }; *.cpp : sequence seq( id(), ( tag::sequence::a = a_value, tag::sequence::arg_method = sequence_arg::a() ) ); So far so good except there is redundancy of information about which method to use, so I'm looking for a way to be able to call say sequence seq( id(), ( tag::sequence::a = a_value ) ) Any suggestion?

2 2

boost fusion and/or boost parameter: open ended question about constructing object from a string
by e r 10 Sep '08

10 Sep '08

hi, here's what i'd like to do A] hpp: struct my{ template<typename ArgPack> my(const ArgPack& args):n_(args[tag::n]),k_(args[tag::k]){} } struct argpack{ arglist<???> operator()(const string& str){???} } cpp: string str("n=2; k=1"); my(argpack(str)); In words,I'm looking to construct an ArgPack from a string, what's the appropriate library for this? Does it seem like I should invest in Boost Spirit? B] The above is a simplified version of what i really need, which is, potentially, 1) having to construct a large number of objects (to be pushed at the back of a container) 2) each object taking a large number arguments (not just n and k as above) 3) each object an instance of one of a set of classes (my0,my1,my2,...,myN) each with its specific argument tags (keywords). So I'd like to put all these arguments in a file, each line corresponding to an object, rather than have a messy cpp file. this is all very open-ended, but so reads the subject title... thanks!

2 5

fusion/adapted/mpl.hpp
by e r 10 Sep '08

10 Sep '08

Hi, I would need this: // a) typedef fusion::vector<...> input0_type; typedef mpl::transform( input0_type, F0 )::type result0_type; //b) typedef fusion::vector<...> resul1_type; result1_type result1 = fusion::transform( result0_type(), f1 ); Of course a) is not allowed, but I guess I can do: // a) typedef mpl::vector<...> mpl_input0_type; //same elements as input0_type typedef mpl::transform( mpl_input0_type, F0 )::type mpl_result0_type; //b) #include <boost/fusion/adapted/mpl.hpp> #include <boost/fusion/include/mpl.hpp> typedef fusion::vector<...> resul1_type; result1_type result1 = fusion::transform( mpl_result0_type(),//? f1 ); in my case, result1_type = input0_type. So I have to define input0_type and mpl_input0_type separately although they convey the same information. i'd like to get rid of this redundancy. I wished there existed a metafun fusion_to_mpl such that MPL_ASSERT((is_same<fusion_to_mpl<input0_type>::type,mpl_input0_type>)) so that the 1st version of a) could be replaced by typedef mpl::transform( fusion_to_mpl<input0_type>::type, F0 )::type mpl_result0_type; and keep the second version of b) any help appreciated. thanks!

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Re: [Boost-users] [bind] [multi-index] Create type of pointer to overloaded erase method
by JOAQUIN M. LOPEZ MUÑOZ 10 Sep '08

10 Sep '08

________________________________________ De: boost-users-bounces(a)lists.boost.org [boost-users-bounces(a)lists.boost.org] En nombre de Steven Watanabe [watanabesj(a)gmail.com] Enviado el: miércoles, 10 de septiembre de 2008 18:54 Para: boost-users(a)lists.boost.org Asunto: Re: [Boost-users] [bind] [multi-index] Create type of pointer to overloaded erase method > AMDG > > Peter Barker wrote: > > RecordsContainer::size_type (RecordsContainer::*erase)(unsigned int) = > > &RecordsContainer::erase; > > > > but it failed to compile. Visual Studio 2003 gives me the following > > error on the above line: > > <snip> > > > > The following compiles for me with msvc 9.0 > > int main() { > RecordsContainer::size_type (RecordsContainer::*erase)(unsigned int) = > &RecordsContainer::erase; > } Oddly enough, it fails with MSVC++ 8.0 (though it shouldn't since your call_traits analysis is correct): error C2440: 'initializing' : cannot convert from 'overloaded-function' to 'boost::multi_index::detail::ordered_index<KeyFromValue,Compare,SuperMeta, TagList,Category>::size_type (__thiscall boost::multi_index::multi_index_container<Value,IndexSpecifierList>::* )(unsigned int)' [...] The following is bulletproof and has the added benefit of its immunity against future slight changes in the interfaces (like, for instance, erase(key) getting templatized): template<typename Container,typename Key> typename Container::size_type container_erase(Container& c,const Key& k) { return c.erase(k); } int main() { RecordsContainer::size_type (*erase)(RecordsContainer&,const unsigned int&) = &container_erase; } Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[serialization] How to deal with bit fields?
by Sebastian Knopp 10 Sep '08

10 Sep '08

Hello, I am a new user of the serialization library and find it is a very comfortable solution. But I met a problem concerning the serialization of bit fields. For example, look at the following: struct A { int a : 1; int b : 7; }; Serialization using the following code does not work, because bitfields can not be passed by reference. template<class Archive> void serialize(Archive& ar, A& theA, const unsigned int version) { ar & make_nvp("a", theA.a); ar & make_nvp("b", theA.b); } So, I use this workaround: template<class Archive> void serialize(Archive& ar, A& theA.a, const unsigned int version) { bool myA; int myB; if (!Archive::is_loading::value) { myA = (theA.a == 1); myB = theA.b; } ar & make_nvp("a", myA); ar & make_nvp("b", myB); if (Archive::is_loading::value) { theA.a = myA ? 1 : 0; theA.b = myB; } } Do you have any suggestions how a more elegant solution could look like? Thanks and bye, Sebastian Knopp

2 1

[dataflow] Filter with multiple slots
by Manuel Jung 10 Sep '08

10 Sep '08

Hey, I want to define my own filter, which can take different signatures. It should take a Url (e.g. std::string, for me an unicode type) and use a difault timeout or it should take both. There is an tutorial for multiple slots, when using a consumer, but i need a filter and i am wondering how i should define the signature of the filter then? (overlaoding of the operator() method needs to be done of course. Kind Regards Manuel

2 1

static linkage of filesystem lib under linux
by Ottmar Buennemeyer 10 Sep '08

10 Sep '08

Hello, We have problems with using the static filesystem lib under linux. We use filesystem as static library in a shard library. Example: libfilesystem.a used for shared library libTestBoostStatic.so No errors during build of library libTestBoostStatic.so. Afterwards we use libtest.so in the application UseTestBoostStatic. During the linking of the application we get the following error message: Invoking: GCC C++ Linker g++ -L/home/ROSENINSPECTION/AlKeller/src/SDES/Test/TestBoostStatic/Debug -L/usr/lib64 -Wl,-static -lboost_filesystem-mt -lboost_regex-mt -Wl,-call_shared -o"UseTestBoostStatic" ./UseTestBoostStatic.o -lTestBoostStatic /home/ROSENINSPECTION/AlKeller/src/SDES/Test/TestBoostStatic/Debug/libTestBoostStatic.so: undefined reference to `boost::filesystem::detail::dir_itr_increment(void*&, void*&, std::basic_string<char, std::char_traits<char>, std::allocator<char> >&, boost::filesystem::file_status&, boost::filesystem::file_status&)' /home/ROSENINSPECTION/AlKeller/src/SDES/Test/TestBoostStatic/Debug/libTestBoostStatic.so: undefined reference to `boost::filesystem::detail::dir_itr_close(void*&, void*&)' /home/ROSENINSPECTION/AlKeller/src/SDES/Test/TestBoostStatic/Debug/libTestBoostStatic.so: undefined reference to `boost::filesystem::detail::dir_itr_first(void*&, void*&, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::basic_string<char, std::char_traits<char>, std::allocator<char> >&, boost::filesystem::file_status&, boost::filesystem::file_status&)' /home/ROSENINSPECTION/AlKeller/src/SDES/Test/TestBoostStatic/Debug/libTestBoostStatic.so: undefined reference to `boost::filesystem::detail::not_found_error' collect2: ld returned 1 exit status make: *** [UseTestBoostStatic] Error 1 We use the boost version 1.34.1 GCC Version: 4.1.2 20061115 (pre release) What's wrong with our configuration? Thanks in advance, Ottmar

2 1

[Boost_users][date_time] Updating ptime after it's been constructed
by Ryan McConnehey 10 Sep '08

10 Sep '08

Hi, Currently I'm creating a boost date_time object as follows: boost::shared_ptr<boost::posix_time::ptime> time(new boost::posix_time::ptime(boost::posix_time::microsec_clock::local_time())); Now that the ptime object has been created how do I update the boost pointer with a new local_time? There doesn't seem to be any function calls or operators that allow the setting of time. The only operators seem to allow you to offset the time not replace it. Ryan

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Re: [Boost-users] Comparing two vectors element by element
by Gevorg Voskanyan 10 Sep '08

10 Sep '08

Sean Farrow wrote: > It's not allower, the sizes aren't identical. > Sean. Then I think you can perfectly use the function below: bool bitset_vector_less( const std::vector< std::bitset< 6 > > & lhs, const std::vector< std::bitset< 6 > > & rhs ) { assert( lhs.size() == rhs.size() ); return std::equal( lhs.begin(), lhs.end(), rhs.begin(), BitSetComp() ); } where BitSetComp is the predicate you have shown earlier. HTH, Gevorg

2 1

Periodic Timer
by amit khandelwal 10 Sep '08

10 Sep '08

I see that we have a deadline timer in boost. I am looking for a periodic timer. I see that there is a sample code in boost website to simulate a periodic timer. Over a period of time I think it will probably cause some slippage. I am looking at microsecond granularity Can someone please advise? #include <iostream> #include <boost/asio.hpp> #include <boost/thread.hpp> #include <boost/bind.hpp> #include <boost/date_time/posix_time/posix_time.hpp> class printer { public: printer(boost::asio::io_service& io) : timer1_(io, boost::posix_time::microseconds(10)), count_(0) { timer1_.async_wait(boost::bind(&printer::print1, this)); } ~printer() { std::cout << "Final count is " << count_ << "\n"; } void print1() { if (count_ < 100) { timer1_.expires_at(timer1_.expires_at() + boost::posix_time::microseconds(10)); timer1_.async_wait(boost::bind(&printer::print1, this)); std::cout << "Timer 1: " << count_ << "\n"; ++count_; } } private: boost::asio::deadline_timer timer1_; int count_; }; int main() { boost::asio::io_service io; printer p(io); boost::thread t(boost::bind(&boost::asio::io_service::run, &io)); io.run(); t.join(); return 0; } -- ------------------------------------------------------------------- Ph : (732) 647 5679 Email: khandelwal.amit(a)gmail.com Web: http://khandelwal.amit.googlepages.com/home -------------------------------------------------------------------

2 4

[graph] Overkill to use graph library for 'small' graphs?
by Rainer Thaden 10 Sep '08

10 Sep '08

Hi all, I have to manage connections between different items in an audio control software. Currently, I am using several maps to manage "connections". I was thinking of using a graph for this but there are several questions arising. Maybe, someone can enlighten this: I am controlling a hardware which has several inputs and outputs and between it a layer of nodes. The inputs are connected to the nodes as well as the outputs. An input can be connected to several nodes, an output only to one node. So, the graph has to represent connections between inputs, nodes, and outputs. (Actually, there are more layers, but to keep it simple I show only these 3). The inputs, outputs, etc. in the end are integers, which are sent to the device. I represent them as enums. So I have, e.g. enum Inputs{ Input1 = 0, Input2, InputNone }; enum Nodes{ NodeM=0, NodeN, NodeNone }; enum Outputs{ AnalogOut1 = 0, AnalogOut2 OutputNone }; Now, to use graphs, I have to define vertices. These have to be of "one" type, as far as I understand that. How do I use the enums as shown above? A vertice-value may be in enum Inputs or Nodes or Outputs. Do I have to use a graph with elements of type ints and cast them to my enums? From the introduction to BGL, modified: const int num_vertices = InputNone + NodeNone + OutputNone; // writing out the edges in the graph typedef std::pair<int, int> Edge; Edge edge_array[] = { Edge(Input1,NodeM), Edge(Input2,NodeN), Edge(AnalogOut1,NodeM), Edge(AnalogOut2,NodeN)}; const int num_edges = sizeof(edge_array)/sizeof(edge_array[0]); // declare a graph object Graph g(num_vertices); // add the edges to the graph object for (int i = 0; i < num_edges; ++i) add_edge(edge_array[i].first, edge_array[i].second, g); When I e.g. need all vertices, connected to NodeM, I get two ints. One of them represents a member of enum Inputs, the other one a member of enum Outputs. Their numbers overlap, so I can not tell which is an Input and which is an Output (the hardware device needs the numbers starting from 0). Any idea how do solve this? Secondly, is there a big advantage of using a graph? There are about 25 different inputs, 8 nodes and 10 outputs and 2-3 additional layers. It may be more elegant to use one graph instead of several maps. I can not estimate the effort and performance of the graph. Would it be overkill in both, performance and time to implement to use a graph for that? Thanks in advance and regards, Rainer

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Re: [Boost-users] Comparing two vectors element by element
by Gevorg Voskanyan 10 Sep '08

10 Sep '08

Sean Farrow wrote: > Hi Gevorg: > In this case it's the second, for more background for interest: > Each vector represents a braille cell. > A braille cell has 6 dots hence the std::bitset<6> so: > A vector can have up to 6 bitsets, each bitset represents one dots > state. > Hth. > Sean. Ok, what happens when a vector having 4 bitsets is compared with one having 6: - 4 bitsets of the first vector are compared with the first 4 bitsets of the second vector, ignoring last 2 elements? - The first vector is considered the lesser because it has fewer elements? - Is this not allowed? - something else? Best Regards, Gevorg

2 1

Boost.spirit, boost.tokenizer or boost.regex
by Sean Farrow 10 Sep '08

10 Sep '08

Hi: I am currently in the process of needing to transform some input. I need to transform voice commands passed to a dll to strings of text inserted to an application. One voice command might be: "skip 5 lines". In this case the skip translates o sk, the 5 remains as it is, and there is nothing printed for the lines part of the command. Which boost library would be the best suited to this, boost.regex, boost.tokenizer or boost.spirit? Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3431 (20080910) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

1 0

Re: [Boost-users] Comparing two vectors element by element
by Gevorg Voskanyan 10 Sep '08

10 Sep '08

Sean Farrow wrote: > Hi: > The code doesn't compile here as std:bitsetdoesn't define the < > operator according to visual studio. I have a custom operator defined as > a structure: > struct BitSetComp > { > bool operator()(const std::bitset<6>& lhs, const std::bitset<6>& > rhs) const > { > return lhs.to_ulong() < rhs.to_ulong(); > } > }; > How can I use this in the code you providee, or do I need to redefine in > a certain way? > Cheers > Sean. [snip] Hi Sean, The answer depends on how you define one vector being less than another. E.g. given the following vectors: typedef std::bitset< 6 > my_bitset; typedef std::vector< my_bitset > my_bitset_vector; my_bitset_vector v1 = { my_bitset( "1100" ), my_bitset( "1101" ) }, v2 = { my_bitset( "1110" ), my_bitset( "1000" ) }, v3 = { my_bitset( "1101" ), my_bitset( "1111" ), my_bitset( "1010" ) }, v4 = { my_bitset( "1100" ), my_bitset( "1101" ), my_bitset( "1001" }; how shall these vectors compare to each other? #1. Lexicographical comparison - v1 < v2 is true, v1 < v3 is true, v2 < v3 is false, v1 < v4 is true, ... #include <algorithm> bool bitset_vector_less_1( const my_bitset_vector& lhs, const my_bitset_vector& rhs ) { return std::lexicographical_compare( lhs.begin(), lhs.end(), rhs.begin(), rhs.end(), BitSetComp() ); } #2. Each element of the first vector shall be less than the correponding element of the second vector - v1 < v2 is false, v2 < v1 is false, v4 < v3 is true, (here it is not immediately clear how would one compare vectors of different size such as v1 and v3) bool bitset_vector_less_2( const my_bitset_vector& lhs, const my_bitset_vector& rhs ) { assert( lhs.size() == rhs.size() ); return std::equal( lhs.begin(), lhs.end(), rhs.begin(), BitSetComp() ); } If you mean something else, explain your requirement with more detail and I will try to offer some more help. HTH, Best Regards, Gevorg P.S. Sorry but the answer is not strictly boost-related

3 2

Comparing two vectors element by element
by Sean Farrow 10 Sep '08

10 Sep '08

Hi: I need to compare two vectors. I already have a function to compare two individual elements (std::bitsets) in this case. Can I use boost.foreach to do this, or is there a better way. I need to know whether vector one, is less than vector two. Any help apreciated. Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3428 (20080909) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

2 1

[asio] Error: terminate called after throwing an instance of
by Fabio Locati 10 Sep '08

10 Sep '08

Hi guys, I'm a new user of boost, and even newer of boost.asio. I create this code: http://codepad.org/DXLhsEtW (read.cpp) http://codepad.org/xlGDzgDC (read.h) http://codepad.org/DayP6oOB (http.h) and when I compile with: c++ read.cpp -o read /usr/local/lib/libboost_regex-gcc42-mt-1_36.so -I /usr/local/include/boost-1_36/ /usr/local/lib/libboost_system-gcc42-mt.so -O3 it compiles without any problems, but when I run it, it returns this: http://codepad.org/ad96WiPp I'm not getting why, someone have some idea? Thankyou for your time, Fabio A Locati

1 0

Visual Studio 9.0 Express & boost 1.36 linker issues
by Alfonso Urdaneta 10 Sep '08

10 Sep '08

1. Build boost from scratch. C:\boost\boost_1_36_0>bjam --build-dir="c:\tmp\build-boost" --toolset=msvc --build-type=complete stage C:\boost\boost_1_36_0>bjam --build-dir="c:\tmp\build-boost" --toolset=msvc --build-type=complete install 2. Create a windows form application. add nothing but the line #include <boost/thread.hpp> 3. Update project re: inc and lib dirs. 4. link. Error output follows: 1>------ Build started: Project: b136_test, Configuration: Debug Win32 ------ 1>Linking... 1>b136_test.obj : error LNK2028: unresolved token (0A00000E) "public: virtual char const * __clrcall boost::thread_resource_error::what(void)const " (?what@thread_resource_error@boost@@$$FUBMPBDXZ) referenced in function "void __clrcall `dynamic initializer for 'const boost::thread_resource_error::`vftable'''(void)" (???__E??_7thread_resource_error@boost@@6B@@@YMXXZ@?A0xa2903452@@$$FYMXXZ) 1>b136_test.obj : error LNK2028: unresolved token (0A00000F) "public: virtual char const * __clrcall boost::lock_error::what(void)const " (?what@lock_error@boost@@$$FUBMPBDXZ) referenced in function "void __clrcall `dynamic initializer for 'const boost::lock_error::`vftable'''(void)" (???__E??_7lock_error@boost@@6B@@@YMXXZ@?A0xa2903452@@$$FYMXXZ) 1>b136_test.obj : error LNK2028: unresolved token (0A00001E) "public: virtual __clrcall boost::lock_error::~lock_error(void)" (??1lock_error@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::lock_error::`vector deleting destructor'(unsigned int)" (??_Elock_error@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2028: unresolved token (0A00003B) "public: virtual __clrcall boost::thread_exception::~thread_exception(void)" (??1thread_exception@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::thread_exception::`vector deleting destructor'(unsigned int)" (??_Ethread_exception@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2028: unresolved token (0A00003C) "public: virtual __clrcall boost::thread_resource_error::~thread_resource_error(void)" (??1thread_resource_error@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::thread_resource_error::`vector deleting destructor'(unsigned int)" (??_Ethread_resource_error@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2019: unresolved external symbol "public: virtual __clrcall boost::thread_resource_error::~thread_resource_error(void)" (??1thread_resource_error@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::thread_resource_error::`vector deleting destructor'(unsigned int)" (??_Ethread_resource_error@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2019: unresolved external symbol "public: virtual __clrcall boost::thread_exception::~thread_exception(void)" (??1thread_exception@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::thread_exception::`vector deleting destructor'(unsigned int)" (??_Ethread_exception@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2019: unresolved external symbol "public: virtual __clrcall boost::lock_error::~lock_error(void)" (??1lock_error@boost@@$$FUAM@XZ) referenced in function "public: virtual void * __clrcall boost::lock_error::`vector deleting destructor'(unsigned int)" (??_Elock_error@boost@@$$FUAMPAXI@Z) 1>b136_test.obj : error LNK2019: unresolved external symbol "public: virtual char const * __clrcall boost::lock_error::what(void)const " (?what@lock_error@boost@@$$FUBMPBDXZ) referenced in function "void __clrcall `dynamic initializer for 'const boost::lock_error::`vftable'''(void)" (???__E??_7lock_error@boost@@6B@@@YMXXZ@?A0xa2903452@@$$FYMXXZ) 1>b136_test.obj : error LNK2019: unresolved external symbol "public: virtual char const * __clrcall boost::thread_resource_error::what(void)const " (?what@thread_resource_error@boost@@$$FUBMPBDXZ) referenced in function "void __clrcall `dynamic initializer for 'const boost::thread_resource_error::`vftable'''(void)" (???__E??_7thread_resource_error@boost@@6B@@@YMXXZ@?A0xa2903452@@$$FYMXXZ) 1>C:\code\merlot\av8b\software\prototypes\b136_test\Debug\b136_test.exe : fatal error LNK1120: 10 unresolved externals 1>Build log was saved at "file://c:\code\merlot\av8b\software\prototypes\b136_test\b136_test\Debug\BuildLog.htm" 1>b136_test - 11 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Verified that thread stuff is there C:\boost\lib>dir *thread* Volume in drive C has no label. Volume Serial Number is 1CFE-113F Directory of C:\boost\lib 09/08/2008 10:56 AM 35,328 boost_thread-vc90-mt-1_36.dll 09/08/2008 10:56 AM 31,348 boost_thread-vc90-mt-1_36.lib 09/08/2008 10:41 AM 52,736 boost_thread-vc90-mt-gd-1_36.dll 09/08/2008 10:41 AM 31,634 boost_thread-vc90-mt-gd-1_36.lib 09/08/2008 10:41 AM 31,634 boost_thread-vc90-mt-gd.lib 09/08/2008 10:56 AM 31,348 boost_thread-vc90-mt.lib 09/08/2008 11:18 AM 312,458 libboost_thread-vc90-mt-1_36.lib 09/08/2008 11:07 AM 1,281,058 libboost_thread-vc90-mt-gd-1_36.lib 09/08/2008 11:07 AM 1,281,058 libboost_thread-vc90-mt-gd.lib 09/08/2008 11:42 AM 353,712 libboost_thread-vc90-mt-s-1_36.lib 09/08/2008 11:42 AM 353,712 libboost_thread-vc90-mt-s.lib 09/08/2008 11:28 AM 1,270,890 libboost_thread-vc90-mt-sgd-1_36.lib 09/08/2008 11:28 AM 1,270,890 libboost_thread-vc90-mt-sgd.lib 09/08/2008 11:18 AM 312,458 libboost_thread-vc90-mt.lib 14 File(s) 6,650,264 bytes 0 Dir(s) 834,019,328 bytes free Suggestions for next step in figuring out what the problem is ? -- alfonso e. urdaneta _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ This e-mail and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this e-mail in error please notify the originator of the message. This footer also confirms that this e-mail message has been scanned for the presence of computer viruses. Any views expressed in this message are those of the individual sender, except where the sender specifies and with authority, states them to be the views of Indra Systems, Inc.

2 1

Re: [Boost-users] Comparing two vectors element by element
by Peter Barker 10 Sep '08

10 Sep '08

On Tue, Sep 9, 2008 at 5:15 PM, Peter Barker <newbarker(a)gmail.com> wrote: > On Tue, Sep 9, 2008 at 4:55 PM, Sean Farrow > <sean.farrow(a)seanfarrow.co.uk> wrote: >> Hi: >> I need to compare two vectors. I already have a function to compare two >> individual elements (std::bitsets) in this case. Can I use boost.foreach >> to do this, or is there a better way. >> I need to know whether vector one, is less than vector two. >> >> Any help apreciated. >> Cheers >> Sean. > > Just use == as you do with built in data types e.g.: > > #include <vector> > #include <iostream> > > int main() > { > std::vector<int> v1; > std::vector<int> v2; > > if(v1 == v2) > std::cout << "They're the same" << std::endl; > } > Oops - sorry - I posted too quickly. Let's try again... Just use the < operator as you would with built in types. e.g.: #include <vector> #include <iostream> int main() { std::vector<int> v1; v1.push_back(5); std::vector<int> v2; v2.push_back(6); if(v1 < v2) std::cout << "v1 is smaller than v2" << std::endl; }

2 1

boost::parameter -- merging two ArgPacks
by e r 10 Sep '08

10 Sep '08

hello, here's what i'm looking to do: template<typename ArgPack> result_type unary_fun(const ArgPack& args){ //typically calls args[some_tag] } template<typename ArgPack1,typename ArgPack2> result_type binary_fun(const ArgPack1& args1,const ArgPack2& args2){ return unary_fun(merge(args1,args2)); } i'm looking to define merge. not familiar enough with arg_list.hpp any help would be appreciated. thanks.

2 2

[serialization] Assertion failed on application exit
by Takeo 10 Sep '08

10 Sep '08

Hello, I'm using boost 1.36 for serialization and everithing goes fine except this strange assertion error when I exit my application (console or window) : assertion failed: NULL != r, file libs\serialization\src\extended_type_info.cpp, line 49 The error occured in debug and release mode and boost is used in a static library called by the application. Have you got any idea of how to get rid of this? Thanks by advance. Emmanuel -- View this message in context: http://www.nabble.com/-serialization--Assertion-failed-on-application-exit-… Sent from the Boost - Users mailing list archive at Nabble.com.

2 3

boost::posix_time::ptime - performance
by amit khandelwal 09 Sep '08

09 Sep '08

For 1 million invocations of boost::posix_time::ptime ptm (boost::posix_time::microsec_clock::local_time() ); // Get current time It takes about 1 sec. However, gettimeofday takes about 300 ms. gettimeofday takes about 300 ms. // struct timeval tv; // gettimeofday(&tv, NULL); Any pointers on why it takes so long? I want to ensure that timestamp call are not expensive. Any suggestion/recommendation? -- ------------------------------------------------------------------- Ph : (732) 647 5679 Email: khandelwal.amit(a)gmail.com Web: http://khandelwal.amit.googlepages.com/home -------------------------------------------------------------------

2 1

Using the operators library
by Sean Farrow 09 Sep '08

09 Sep '08

Hi: Can I use the operators library to override operators for the std::bitset class. If so how do I do this? Cheers Sean. __________ Information from ESET NOD32 Antivirus, version of virus signature database 3426 (20080908) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

2 1

[multi_index_container] push_back?
by Robert Jones 09 Sep '08

09 Sep '08

Still having a little teething trouble with multi_index_container. This code, #include <string> #include <boost/multi_index_container.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/identity.hpp> #include <boost/multi_index/member.hpp> using namespace boost; using namespace boost :: multi_index; struct Employee { int id; std :: string name; }; bool operator < ( Employee const & l, Employee const & r ) { return l.id < r.id; } int main( ) { typedef multi_index_container< Employee, indexed_by< ordered_unique<identity<Employee> >, ordered_non_unique<member<Employee, std :: string, & Employee :: name> > > > EmployeeSet; Employee employees[ ] = { { 1, "Adam" }, { 2, "Craig" }, { 3, "Brian" }, { 4, "Dave" }, }; // EmployeeSet eSet( employees, employees + sizeof( employees ) / sizeof( Employee ) ); EmployeeSet eSet; std :: copy( employees, employees + sizeof( employees ) / sizeof( Employee ), std :: back_inserter( eSet ) ); return 0; } Gives me an error stating there is no push_back method on the container. /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/bits/stl_iterator.h:364: error: 'class boost::multi_index::multi_index_con tainer<Employee, boost::multi_index::indexed_by<boost::multi_index::ordered_unique<boost::multi_index::identity<Employee >, mpl_::na, mpl_::na>, boost::multi_index::ordered_non_unique<boost::multi_index::member<Employee, std::string, &Employ ee::name>, mpl_::na, mpl_::na>, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na , mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, std::allocator<Employee> >' has no member named 'push_back' is there something I'm missing out? Thanks, Rob.

4 5

Re: [Boost-users] How the boost documentation is generated? (Peng Yu)
by Rodolfo Federico Gamarra 09 Sep '08

09 Sep '08

Hi Peng, Did you look at these webpages? http://www.boost.org/doc/libs/1_36_0/doc/html/boostbook.html http://www.boost.org/doc/libs/1_36_0/tools/quickbook/doc/html/index.html http://www.docbook.org/ Maybe you find them helpful. Thanks. -- Rodolfo Federico Gamarra

2 1

[string algorithms] finding last digit
by Peter Barker 09 Sep '08

09 Sep '08

Hello, I have the following program: #include <string> #include <boost/algorithm/string/classification.hpp> #include <boost/algorithm/string/finder.hpp> int main() { std::string str("12.5e"); boost::last_finder(str,boost::is_digit()); // <--- is this sort of right? } What I'm trying to do is find the last occurence of a digit in my string (and learn a bit more about Boost.StringAlgorithms!). Am I going down the correct route here, and if so would someone be so kind to add to my program to show how I could obtain and output the index? The call operator for last_finder accepts two paramters which has thrown me as I thought the range was defined at construction. Thanks in advance, Pete

2 2

[multi_index_container] Compiling the examples
by Robert Jones 09 Sep '08

09 Sep '08

Trying to multi_index_container I'm getting these compile errors. Apart from #include <string> and using namespace boost this lifted verbatim from the example documentation. #include <string> struct employee { int id; std::string name; employee(int id,const std::string& name):id(id),name(name){} bool operator<(const employee& e)const{return id<e.id;} }; #include <boost/multi_index_container.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/identity.hpp> #include <boost/multi_index/member.hpp> using namespace boost; // define a multiply indexed set with indices by id and name typedef multi_index_container< employee, indexed_by< // sort by employee::operator< ordered_unique<identity<employee> >, // sort by less<string> on name ordered_non_unique<member<employee,std::string,&employee::name> > > > employee_set; My error is multi.cpp:23: error: `indexed_by' was not declared in this scope multi.cpp:25: error: `ordered_unique' was not declared in this scope multi.cpp:25: error: `identity' was not declared in this scope multi.cpp:25: error: template argument 2 is invalid multi.cpp:25: error: expected unqualified-id before '>' token multi.cpp:25: error: expected `,' or `;' before '>' token I'm using Boost 1.36 and gcc 3.4.4 (maybe this too old?). Can anyone tell me what I'm doing wrong? Thanks, Rob. -- ACCU - Professionalism in programming - http://www.accu.org

2 1

How the boost documentation is generated?
by Peng Yu 09 Sep '08

09 Sep '08

Hi, I'm wondering how the boost documentation for different packages is generated consistently and with code snippets extracted from the source code. Can somebody give a pointer? Thanks, Peng

1 0

Problem with iostreams and zlib
by Alfred Kohl 09 Sep '08

09 Sep '08

Hi! the gzip_decompressor sometimes fails with Z_BUF_ERROR wrapped in zlib_error(). I'm using boost-1.36.0 and zlib-1.2.3, both statically linked. Stream setup is as follows: std::ifstream filein("testfile"); boost::iostreams::filtering_streambuf<boost::iostreams::input> strbuf; strbuf.push(boost::iostreams::gzip_decompressor()); strbuf.push(filein); std::istream input(&strbuf); do { char buf[4096]; input.read(&buf, 4096); } while (input.gcount() > 0); For one particular file, read() will fail after reading about 2 MB (of 3 MB total file size). The file decompresses fine with external tools and contains mainly zeros. The error happens in (boost/iostreams/filter/zlib.hpp): bool zlib_decompressor_impl<Alloc>::filter ( const char*& src_begin, const char* src_end, char*& dest_begin, char* dest_end, bool /* flush */ ) { before(src_begin, src_end, dest_begin, dest_end); int result = inflate(zlib::sync_flush); after(src_begin, dest_begin, false); zlib_error::check(result); // <--- return result != zlib::stream_end; } src_begin and src_end both point to the same location! I'm not an expert with zlib but this looks wrong to me... Re-compressing the file with an external tool does not help. Any ideas? Cheers, Alfred. -- GMX Kostenlose Spiele: Einfach online spielen und Spaß haben mit Pastry Passion! http://games.entertainment.gmx.net/de/entertainment/games/free/puzzle/61691…

1 0

[boost:regex]an compiler error when use boost1_36 in application
by gj_uestc 09 Sep '08

09 Sep '08

hi,all When I use "libboost_regex-iw-mt-s-1_36.lib" in my application , I got such compiler error "cannot open file 'stlport_static.5.1.lib'".Should I need to find stlport_static.5.1.lib and add it by my self? Is there any Macro that may let myself choose whether or not use the 'stlport_static.5.1.lib'? PS:The boost lib I used is compilered with ICU,Is there any chance that the 'stlport_static.5.1.lib' is brought by useage of ICU? Thanks Juan

3 6

Re: [Boost-users] Catching boost::thread_interrupted
by rbock＠eudoxos.de 09 Sep '08

09 Sep '08

Hi, sorry, forgot to send the attachment in the original positing... Regards, Roland Hi, currently I am making my first steps using Boost.Thread (1.36.0). The interrupt feature looks very cool, so I tried to use it, but somehow failed to catch boost::thread_interrupted. The code is attached to this mail. I was expecting to see something like Thread 0x60b050 got interrupted Thread 0x60b3e0 got interrupted Instead I got Thread 0x60b050 caught something else Thread 0x60b3e0 caught something else Can somebody please enlighten me? Thanks and regards, Roland

6 14

[Asio] Erratic results with io_service + deadline_timer
by John Zwinck 09 Sep '08

09 Sep '08

Today I tried using Boost.Asio to make a function get called at a particular time of day. My work included some tests, which usually passed but sometimes failed. I've boiled it down below. I'm using gcc 4.0.3 and Boost 1.35 on Linux 2.6.22 (Ubuntu Dapper 32-bit i686, quad-core CPU). I compiled the following code with g++ -lboost_thread -lboost_date_time -lboost_system : #include <boost/system/error_code.hpp> #include <boost/thread/thread.hpp> #include <boost/asio/io_service.hpp> #include <boost/asio/deadline_timer.hpp> #include <boost/date_time/posix_time/posix_time.hpp> using namespace boost; using namespace boost::asio; using namespace boost::posix_time; bool g_called = false; io_service g_svc; void func(boost::system::error_code ec) { g_called = true; } void work() { for(;;) { g_svc.run(); } } int main() { thread thr(work); #ifdef FAIL // if defined, causes program to always assert this_thread::sleep(milliseconds(1)); #endif deadline_timer tmr(g_svc, second_clock::local_time() + seconds(1)); tmr.async_wait(&func); // expected to wait 1 second then call func this_thread::sleep(milliseconds(1500)); assert(g_called); } I think my first issue was that I didn't recognize the need to call io_service::run in a loop. The docs<http://www.boost.org/doc/libs/1_35_0/doc/html/boost_asio/reference/io_servi…>don't make this clear at all, stating that it will "Run the ... event processing loop," but I figured from reading the source that the loop in my own code was needed. Anyway, that didn't fix it. What I'm expecting here is that my callback function will be invoked about a second after registration, and it will set the flag which is then checked half a second later. When compiled as-is, this (usually) works. However, when compiled with -DFAIL, which just adds a tiny sleep in a place I'd think it would not matter, it fails always. Surely I'm doing something wrong. Or is the combination of this (new) library and my system just not working correctly (something I rather doubt given my past experience with Boost)?

2 1

Re: [Boost-users] [boost:regex]an compiler error when use boost1_36 inapplication
by gmail 09 Sep '08

09 Sep '08

1 0

Is there a function to compute the determinant of a square matrix?
by Peng Yu 09 Sep '08

09 Sep '08

Hi, boost has ublas. I'm wondering if there is a function to compute the determinant of a square matrix in boost? Thanks, Peng

1 0

mpl::transform<...> --- compile error: is not derived from type
by e r 09 Sep '08

09 Sep '08

hi, here's the problem i have: struct my{ template<typename UInt> struct apply{ typedef mpl::int_<UInt::value> type; }; }; template<int First,int Last> struct id_range{ typedef mpl::transform< mpl::range_c<int,First,Last> , my , mpl::back_inserter< mpl::vector<> > >::type type; /home/er/cpp/boost/random/mcmc/id_range.hpp|32|error: type ‘boost::mpl::transform<boost::mpl::range_c<int, First, Last>, boost::random::mcmc::<unnamed>::my, boost::mpl::back_inserter<boost::mpl::vector<mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na> >, mpl_::na>’ is not derived from type ‘boost::random::mcmc::id_range<First, Last>’| however, for example, this --instead-- compiles fine: struct id_range{ typedef mpl::transform< mpl::range_c<int,1,3> , my , mpl::back_inserter< mpl::vector<> > >::type type; }; any suggestion appreciated. thanks!

2 4

[dataflow][review] loading Dataflow.Signals components from shared libraries
by Stjepan Rajko 09 Sep '08

09 Sep '08

In the Dataflow library / Dataflow.Signals layer review discussions, a few people have mentioned the potential usefulness of loading components at runtime (e.g., from a shared library). I put together a small example of how this could be done for Dataflow.Signals components using the (prototype) Dataflow.Blueprint layer and the Extension library: http://svn.boost.org/svn/boost/sandbox/SOC/2007/signals/libs/dataflow/examp… The component_add.cpp file contains the implementation of a component (that adds two numbers and outputs the result), and the code required to access it through an Extension factory_map. The extension_example.cpp file loads the shared library created from component_add.cpp, instantiates the provided component, and uses it to complete a network. The Blueprint layer is still under development (and has somewhat ugly syntax), but I hope this example can still demonstrate some future possibilities of the Dataflow library with regards to loading components at run-time. It has been tested to work with MSVC 2005. Regards, Stjepan

1 0