March 2007 - Boost-users - lists.preview.boost.org

iostreams use with asio tcp stream?
by Jeff 07 Mar '07

07 Mar '07

Everyone, Will I be able to use an asio tcp stream in an iostream filtering pipeline, so that I can first compress, then encrypt, then send the data over a tcp or udp connection? Thanks, Jeff

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[enable_if] using enable_if to extend std::numeric_limits?
by james.jones＠firstinvestors.com 07 Mar '07

07 Mar '07

Suppose I have a set of templates that have a common interface (each is a model of the same concept, to use that lingo). I'd like to extend std::numeric_limits to support this concept. I'm trying to find a way to use enable_if to do this, but I don't see how. Is this possible? Is there some other trick to doing this? Example with code (not real code): template< class U, class V > class model1; tempalte< class U, class V > class model2; template< class U > is_decimal_type { static const bool value = false; }; template< class U, class V > is_decimal_type < model1<U, V> > { static const bool value = true; }; template< class U, class V > is_decimal_type < model2<U, V> > { static const bool value = true; }; Would like to do this: template< class T > class numeric_limits< T > { // extensions go here }; But only if is_decimal_type<T>::value is true (so that the partial specialization only applies to my concept). Thanks, - James Jones Administrative Data Mgmt. Webmaster 375 Raritan Center Pkwy, Suite A Data Architect Edison, NJ 08837

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[BGL] In what order does out_edge_iterator iterate?
by Shufei Fan 07 Mar '07

07 Mar '07

Hi, In my application, the order in which edges are retreaved is also important to me. So my question is, when I iterate through an vertex's out_edges, do they show up in the order in which the edges are inserted, or any other principals are used in order of iteration? Example: ...... typename graph_traits<Graph>::out_edge_iterator out_i, out_end; typename graph_traits<Graph>::edge_descriptor e; for (tie(out_i, out_end) = out_edges(v, g); out_i != out_end; ++out_i) { e = *out_i; Vertex src = source(e, g), targ = target(e, g); std::cout << "(" << get(vertex_id, src) << "," << get(vertex_id, targ) << ") "; } ...... How are these edges ordered in the output? And is it right all those iterators iterates in the same principals/order? Thanks, Shufei

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[boost::wave] Finding out if a macro is defined
by Ovanes Markarian 07 Mar '07

07 Mar '07

Hello All, using boost::wave (with context initialized as explained in the docs example) and trying to find out if some certain macro is defined leads to 2 errors: 1. Doc for context state: bool is_defined_macro(std::string const &name) const; But the source has no such function definition. I assume the signature was changed to: template <typename IteratorT2> bool is_defined_macro(IteratorT2 const &begin, IteratorT2 const &end) { return macros.is_defined(begin, end); } Trying to fix it and using the std::string::begin() and std::string::end() members to specify the begin and end range result in the error: c:\boost\include\boost-1_33_1\boost\wave\util\cpp_macromap.hpp(331) : error C2228: left of '.get_value' must have class/struct/union type is 'char' c:\boost\include\boost-1_33_1\boost\wave\cpp_context.hpp(150) : see reference to function template instantiation 'bool boost::wave::util::macromap<ContextT>::is_defined<IteratorT2>(const IteratorT &,const IteratorT &)' being compiled with [ ContextT=boost::wave::context<token_groups::str_iter_type,token_groups::lex_iter_type>, IteratorT2=char *, IteratorT=char * ] e:\projects\inpecting_wave\inpecting_wave\header_processor.cpp(177) : see reference to function template instantiation 'bool boost::wave::context<IteratorT,LexIteratorT>::is_defined_macro<char*>(const IteratorT2 &,const IteratorT2 &)' being compiled with [ IteratorT=token_groups::str_iter_type, LexIteratorT=token_groups::lex_iter_type, IteratorT2=char * ] This happens in cpp_macromap.hpp line 331: function source: template <typename ContextT> template <typename IteratorT> inline bool macromap<ContextT>::is_defined(IteratorT const &begin, IteratorT const &end) { // in normal mode the name under inspection should consist of an identifier // only token_id id = token_id(*begin); if (T_IDENTIFIER != id && !IS_CATEGORY(id, KeywordTokenType) && !IS_EXTCATEGORY(id, OperatorTokenType|AltExtTokenType)) { BOOST_WAVE_THROW(preprocess_exception, invalid_macroname, impl::get_full_name(begin, end).c_str(), main_pos); } IteratorT it = begin; error line >>>>>> string_type name ((*it).get_value()); <<<<<< error line typename defined_macros_type::iterator cit(current_macros -> find(name)); if (++it != end) { // there should be only one token as the inspected name BOOST_WAVE_THROW(preprocess_exception, invalid_macroname, impl::get_full_name(begin, end).c_str(), main_pos); } return cit != current_macros -> end(); } I assume compiler dereferences iterator to char and char has no member to get_value. Does anyone have suggestions? With Kind Regards, Ovanes Markarian

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[program_options] ignoring unknown options
by martux 07 Mar '07

07 Mar '07

Hi, I am having some trouble getting program_options to ignore unknown options. As suggested in the documentation I set allow_unregistered() but po::store(po::command_line_parser(argc, argv).options(pd.get()).allow_unregistered().run(), vm); po::notify(vm); still throws boost::program_options::unknown_option. Could anyone please make clear how to do it correctly? -- View this message in context: http://www.nabble.com/-program_options--ignoring-unknown-options-tf3361505.… Sent from the Boost - Users mailing list archive at Nabble.com.

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regex: seem to be missing something here
by Noah Roberts 06 Mar '07

06 Mar '07

fs::path upper("c:/differences", fs::native); fs::path checked(upper/"checked"); assert(fs::exists(upper)); assert(fs::exists(checked)); fs::directory_iterator end; rg::regex rgx("*ps", rg::regex::basic); for (fs::directory_iterator it(upper); it != end; ++it) { if (rg::regex_match(it->string(), rgx)) std::cout << "MATCH: "; else std::cout << "NOMATCH: "; std::cout << it->string() << std::endl; } Supposed to be looking for ps files. tried *\\.ps, which should work but also didn't. Doesn't match any of the strings. One example line of output: NOMATCH: c:/differences/Adj. speed test case 5 (metric units).ps Supposedly regex is greedy, no? It should accept . as a * element and continue to match everything up to ps and ps also...why no worky? Thanks.

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[Boost.Condition]
by Manuel Jung 06 Mar '07

06 Mar '07

Hi, I would like to know the waiting threads for a condition. Is there a way to calculate the number of "wait()"s which would be affected by a notifiy_all()? Maybe nobody needed this before? Or isn't this possible to implement such a thing with boost::condition and i have to count the waiting threads on the application level? Greetings Manuel Jung

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[Serialization] how to use serialization in windows dll
by jiang.yu(mos) 06 Mar '07

06 Mar '07

Hi! I meet trouble in use serialization in dll in dll export a function like hi_dll() void hi_dll() { std::map<std::string,int> m_map; std::ostringstream os; boost::archive::text_oarchive oa(os); oa & m_map; std::cout << os.str() << std::endl; } and in exe there is a function hi_exe() code is the same as hi_dll void hi_exe() { std::map<std::string,int> m_map; std::ostringstream os; boost::archive::text_oarchive oa(os); oa & m_map; std::cout << os.str() << std::endl; } in Debug mode , the exe call both hi_exe() and hi_dll() will assert at extended_type_info.cpp line 71 assert(lookup(eti) == m_self->m_map.end()); vc7.1 boost 1.33.1 link with serialization as dll then what to do? thanks in advance. Best Regards mos

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Problem with graphs - constructor throwing vector::_M_fill_insert
by Tamas Marki 06 Mar '07

06 Mar '07

Hi, I'm having a problem with the graph library. The problematic function looks like this below. Edge is a simple struct with vertex_a, vertex_b and cost as its members. The trick is that I need to process this big graph a few times, each time throwing out some edges and keeping others, hence the reindexing and mapping of these. I've used the graph lib previously, and worked, I'm just unable to find what am I doing wrong this time. Any help would be welcome. Thanks in advance. typedef std::pair<int, int> edge; typedef boost::adjacency_list < boost::listS, boost::vecS, boost::directedS, boost::no_property, boost::property < boost::edge_weight_t, int > > graph_t; typedef boost::graph_traits < graph_t >::vertex_descriptor vertex_descriptor; typedef boost::graph_traits < graph_t >::edge_descriptor edge_descriptor; graph_t* KGMReader::buildGraph (vector<edge>& edgs, vector<int>& weights, vector<int>& vertexmapping, int rootter) { edgs.clear (); weights.clear (); vertexmapping.clear (); for (vector<Edge>::iterator it = edges.begin (); it != edges.end (); ++it) { if (keepEdge (*it, rootter)) { vector<int>::iterator v1 = find (vertexmapping.begin (), vertexmapping.end (), it->vertex_a); vector<int>::iterator v2 = find (vertexmapping.begin (), vertexmapping.end (), it->vertex_b); if (v1 == vertexmapping.end ()) { vertexmapping.push_back (it->vertex_a); v1 = find (vertexmapping.begin (), vertexmapping.end (), it->vertex_a); } if (v2 == vertexmapping.end ()) { vertexmapping.push_back (it->vertex_b); v2 = find (vertexmapping.begin (), vertexmapping.end (), it->vertex_b); } edgs.push_back (edge (v1 - vertexmapping.begin (), v2 - vertexmapping.begin ())); weights.push_back (it->cost); edgs.push_back (edge (v2 - vertexmapping.begin (), v1 - vertexmapping.begin ())); weights.push_back (it->cost); } } qDebug () << "Vertexes: " << vertexmapping.size () << " edges " << edgs.size () << ", weights " << weights.size (); graph_t *g = 0; try { g = new graph_t (edgs.begin (), edgs.end (), weights.begin (), vertexmapping.size ()); } catch (exception& e) { qDebug () << "caught!!! " << e.what (); g = 0; } return g; } -- Tamas Marki

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program_options - save configuration
by Aljaz 06 Mar '07

06 Mar '07

I wonder if there are any functions in boost program options libary to save them back to configuration file? Maybe any example? Thanks for help

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