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Strange errors on Mac OS X
by Baptiste Gaillard 29 Mar '07

29 Mar '07

Hi, I've tried to use boost on MacOS X but encouter strange problems at compilation's time. I wish to use the uBlas library so I've insert this code in an header file. #include <boost/numeric/ublas/matrix.hpp> #include <boost/numeric/ublas/io.hpp> When I try to compile I obtain those errors: /usr/include/c++/4.0.0/complex:131 error: expected unqualified-id before 'double' /usr/include/c++/4.0.0/complex:131 error: abstract declarator '_Tp&' used as declaration ... ... (149 more) I've installed the library using 'apt-get' 'apt-cache search boost' give me that boost-jam boost1.33 boost1.33-shlibs So my version off boost is 1.33 'gcc --version' display i686-apple-darwin8-gcc-4.0.1 (GCC) 4.0.1 (Apple Computer, Inc. build 5367) I'm using a MacBook with a Core 2 Duo processor. So, do you have any idea to solve this problem ? Thanks Baptiste PS: Sorry if it's somtimes difficult to understand my words, I'm french :-) _________________________________________________________________ Personnalisez votre Messenger avec Live.com http://www.windowslive.fr/livecom/

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[iostreams][zlib] zlib compressor filter error
by aldin seh 29 Mar '07

29 Mar '07

Hello, This was my test case: std::ifstream file_stream; std::ofstream dest_stream; file_stream.open(test.txt, std::ios::in | std::ios::binary); dest_stream.open(output.zip, std::ios::out | std::ios::binary); struct zlib_params params; params.level = zlib::default_compression; params.method = zlib::deflated; params.window_bits = zlib::default_window_bits; params.mem_level = zlib::default_mem_level; params.strategy = zlib::default_strategy; params.noheader = true; params.calculate_crc = true; filtering_streambuf<input> test; test.push(zlib_compressor(params)); test.push(file_stream); uint32 copy_size = static_cast<uint32_t>(boost::iostreams::copy(test, dest_stream)); PROBLEM: copy function returns 0 on first call and right copy size on second call. The file size of test.txt is 10KB. It seems that the error is related to read function of the symetrical filter. While commpressing data this function is called to read from filter ( read from file_stream and compress) (Symmetrical.hpp) template<typename Source> std::streamsize read(Source& src, char_type* s, std::streamsize n) { using namespace std; if (!(state() & f_read)) begin_read(); buffer_type& buf = pimpl_->buf_; int status = (state() & f_eof) != 0 ? f_eof : f_good; char_type *next_s = s, *end_s = s + n; while (true) { // Invoke filter if there are unconsumed characters in buffer or if // filter must be flushed. bool flush = status == f_eof; if (buf.ptr() != buf.eptr() || flush) { const char_type* next = buf.ptr(); bool done = !filter().filter(next, buf.eptr(), next_s, end_s, flush); buf.ptr() = buf.data() + (next - buf.data()); if (done) return detail::check_eof(static_cast<streamsize>(next_s - s)); } // If no more characters are available without blocking, or // if read request has been satisfied, return. if ( status == f_would_block && buf.ptr() == buf.eptr() || next_s == end_s ) { return static_cast<streamsize>(next_s - s); } // Fill buffer. if (status == f_good) status = fill(src); } } First the fill function is called to fill data from source to the buffer: (Symmetrical.hpp) template<typename Source> int fill(Source& src) { std::streamsize amt = iostreams::read(src, buf().data(), buf().size()); if (amt == -1) { state() |= f_eof; return f_eof; } buf().set(0, amt); return amt == buf().size() ? f_good : f_would_block; } And here is the problem, if we read from source less than buf().size (indicating eof) f_would_block is returned, but if we use f_eof instead , copy returns right data on first call. (The zlib wraper is never called with signal (flush = true) to finish the compression) Is this a bug or did I something wrong in the above example ? Thanks! _________________________________________________________________ Der neue MSN Messenger. Schreiben.Sehen.Hören. Wie im echten Leben. - http://www.imagine-msn.com/messenger/default2.aspx?locale=de Jetzt herunterladen!

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[serialization] Assertion `new_cid == cid' failed - fails on gcc, works on msvc
by Sohail Somani 29 Mar '07

29 Mar '07

Hi, I am serializing/deserializing a polymorphic class and I am having the above issue upon deserialization where it fails on gcc and works in msvc. The serializer and deserializer are implemented in two different executables. Should that be an issue? All the object files *except* the serialize/deserialize/main functions are the same in both executables. In the gcc case, its comparing new_cid=2 against cid=1 (if that helps at all!) TIA, Sohail

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ptime::from_iso_string() & time_from_string()
by Chris Webster 29 Mar '07

29 Mar '07

Neither of the functions I listed in the title seem to support a time of the format: 1999-12-17T15:15:15 (that is with the 'T' in it). From everything I've seen (wikipedia, w3.org) that is a valid ISO time stamp. Also how do I search the archives? I could get to the page, but no search feature seemed to be present... Thanks, Chris

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[boost::mpl::apply] compiler dependent behavior
by Samuel Charron 28 Mar '07

28 Mar '07

Hi, I'm currently using the apply metafunction, and I have two different behaviors depending on the used compiler. Here is the code : #include <boost/mpl/lambda.hpp> #include <boost/mpl/apply.hpp> #include <boost/mpl/placeholders.hpp> #include <tr1/unordered_set> using namespace boost; using namespace mpl; int main () { apply < std::tr1::unordered_set < _1 , std::equal_to < int>, std::tr1::hash <int>, std::allocator < int > >, int > ::type foo; } With g++ 4.1, there is no error. With g++ 4.2, icc 9.1, an error occurs: - g++ : no class template named 'apply' in 'class std::tr1::unordered_set<mpl_::arg<1>, std::equal_to<int>, std::tr1::hash<int>, std::allocator<int>, false>' - icc: class "std::tr1::unordered_set<boost::mpl::_1, std::equal_to<int>, std::tr1::hash<int>, std::allocator<int>, false>" has no member class "apply" : F::template apply<T1> With g++ 4.3, on some computers, it works, on others it does not. Can you give me some help to make this work ? Thanks, -- Samuel

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returning values in Boost.StateChart
by Federico J. Fernández 28 Mar '07

28 Mar '07

I'm using statechart for a project and I'm trying to do the following without success. I want to get a new event for the statechart when an event is processed. I mean, call process_event with an event and get another event as a result. We tried with different approaches. For example, modifying the passed event (but it's const) and trying to do a custom reaction that returns something (but I had problems too.. don't remember exactly now). The solution for now was to call an interface that it is implemented in all the states.. so I have to do two calls, one for process_event and other for this interface that returns the new event.... and the question is... Is there a better way to do this? Thanks!

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How to download 1.34 RC
by Johan Råde 28 Mar '07

28 Mar '07

I just downloaded and built CVSROOT:pserver:anonymous@boost.cvs.sourceforge.net:/cvsroot/boost. Now I wonder, is this Boost 1.34 RC or the head branch? It seems to me it is the head branch. Where do I find 1.34 RC? I have never used CVS before, so I'm still a bit uncertain exactly how things work. -- Johan Råde

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[mpl] Inheriting from each type in a sequence
by Scott Meyers 28 Mar '07

28 Mar '07

Given some base class, class Base { virtual ~Base(){} }; I want to be able to implement this: template<typename Seq> const Base& createObject() { // return an object that inherits from Base and every type in Seq } The problem is how to create the type of object I want. mpl::inherit is almost what I need, but it takes as template parameters each type to inherit from, and I don't have discrete types, I have a sequence of types. mpl::inherit_linearly takes a sequence and would work for my purposes (which is to create an object that I can later check via dynamic_cast to see if it inherits from a given type), but it works only with forward sequences, and I'll typically have an mpl::set. I could copy the contents of Seq into an mpl::vector and go from there, but that seems kind of gross. Is there a good way to solve this problem that I am overlooking? Thanks, Scott

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[Math Toolkit] MSVC 7.1 issue
by Johan Råde 28 Mar '07

28 Mar '07

I just downloaded the latest version of the Math Toolkit, and tried a simple example: #include <boost/math/distributions/students_t.hpp> boost::math::students_t_distribution<double>(5) dist; When I compile these two lines of code with MSVC 7.1 I get the following error messages: boost\math\special_functions\log1p.hpp(195) : error C2785: 'tools::promote_args<T>::type boost::math::log1p(T)' and 'double boost::math::log1p(double)' have different return types boost\math\special_functions\math_fwd.hpp(246) : see declaration of 'boost::math::log1p' boost\math\special_functions\log1p.hpp(182) : see declaration of 'boost::math::log1p' boost\math\special_functions\log1p.hpp(195) : error C2912: explicit specialization; 'double boost::math::log1p<double>(double)' is not a specialization of a function template boost\math\special_functions\log1p.hpp(183) : fatal error C1903: unable to recover from previous error(s); stopping compilation -- Johan Råde

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String Algo used with std algorithms
by Jason Ivey 28 Mar '07

28 Mar '07

Is there any way to use the string algorithm predicates and other facilities in conjunction with the standard algorithms (IE. for_each, find_if, etc.)? For example I am trying to make the following example work in MSVC8: typedef std::vector<std::string> Strs; Strs strs; strs.push_back("bob"); strs.push_back("lisa"); strs.push_back("eric"); Strs::const_iterator iter = find_if( strs.begin(), strs.end(), boost::bind( &istarts_with, _1, "B", std::locale() ) ); std::cout << "Found: " << std::boolalpha << ( iter == strs.end() ) << std::endl; I would be grateful for any comments or suggestions. Thanks, Jason

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