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Hi
by Can T. Oguz 10 Feb '09

10 Feb '09

Hi, New to boost, glad to get here. Any book recommendations? Can

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[phoenix] compile error using arg1
by Paul Heil 10 Feb '09

10 Feb '09

While expanding my horizons to include functional programming, I've run in to a problem with boost::phoneix lambda functions. I'm trying to use a for_each() command with an overloaded<< operator, but I can't seem to get they types right, and I get a compile error: test.cpp(147) : error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'const boost::phoenix::actor<Eval>' (or there is no acceptable conversion) I've seen example code that's very similiar to this using "cout" instead of the overloaded << operator I have, so I tend to think this is possible. My code is below, can anybody suggest what I could do to fix this? using namespace boost::phoenix; using namespace boost::phoenix::arg_names; class A { public: friend MSXML2::IXMLDOMNode* operator <<( MSXML2::IXMLDOMNode* node, const A& a ); private: // ... }; MSXML2::IXMLDOMNode* operator <<( MSXML2::IXMLDOMNode* node, const A& a ) { // Add stuff from A to 'node' return node; } int main() { MSXML2::IXMLDOMElementPtr pElem; // MSXML2 DOM doc creation removed for brevity std::list< A > theList; // add items to the list... // copy items from the list to the XML element // This does not compile (C2679) std::for_each( theList.begin(), theList.end(), pElem << arg1 ); return 0; } I realize I could write a proxy function like: void A::Print( MSXML2::IXMLDOMNode* t ) const { t << *this; }; and use the bind() within the for_each() std::for_each( theList.begin(), theList.end(), bind( &A::Print, arg1, pElem ) ); but, I'd like to avoid that if possible. If anybody can suggest how to get this done, I would appreciate it. Thanks, PaulH

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[serialization] removing excess XML tags
by Paul Heil 10 Feb '09

10 Feb '09

I'd like to use the boost::serialization library to generate XML that must be read by a third party application. Unfortunately, this application does not like the extra stuff that the serialization library generates. The code below generates XML that looks like this: <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <!DOCTYPE boost_serialization> <boost_serialization signature="serialization::archive" version="5"> <MYTAG class_id="0" tracking_level="0" version="0"></MYTAG> </boost_serialization> What I need is XML that looks more like this: <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> <MYTAG></MYTAG> What can I do to eliminate the extra stuff? Thanks, PaulH class MyClass { private: friend class boost::serialization::access; template<class Archive> void serialize(Archive &ar, const unsigned int version){}; public: MyClass(){}; friend std::ostream & operator<<(std::ostream &os, const MyClass &gp); virtual ~MyClass(){}; }; int main( int argc, _TCHAR* argv[] ) { MyClass mc; std::ofstream ofs("MyFile.xml"); boost::archive::xml_oarchive oa(ofs); oa << boost::serialization::make_nvp( "MYTAG", mc ); return 0; }

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[thread] C++/CLI C# mixed code: linking to libthread yields runtime exception
by Markus Werle 10 Feb '09

10 Feb '09

Hi! I am pretty sure this is an issue beyond boost, rather one of those numerous pitfalls on the way to the M$-promised land called CanUseOldCodeAndCppInDotNet. OTOH I have hope that someone knows about some workaround, OK, here the facts: Win32, XP SP3, using Visual Studio 2008 SP1 with boost_1_37_0 I create a solution containing a C++/CLI project and a C# project, which references the C++/CLI project. Now if the C++/CLI project simply links to libboost_thread*, either via autolink or via explicit configuration, the compiler creates an executable which fails to start in both configurations, Debug and Release. The debugger catches a System.BadImageFormatException. Something went plain wrong. OTOH adding the source files contained in \libs\thread\src\win32 to the project, defining BOOST_ALL_NO_LIB and adding --- #pragma managed(push, off) extern "C" void tss_cleanup_implemented(void) {} #include <boost/thread/thread.hpp> #pragma managed(pop) --- in a cpp file yields a working executable. Scratching my head. Do you have any hint why linking to libboost_thread leads to this weird behaviour? Any idea what I might try? I can provide a stripped down project solution as zip-file on request. regards, Markus [keywords C# C++/CLI CSharp mixed thread boost System.BadImageFormatException]

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[solved] Using Boost in C++/CLI and C# mixed code environment
by Markus Werle 10 Feb '09

10 Feb '09

Hi! With the help of Anthony Williams and Hansi plus a step by step fiddling with the Visual Studio settings I finally managed (sic!) to get C++ and Boost playing nicely in a mixed C++/CLI plus C# code setting. Phew. Went to hell and came back again. Disclaimer: This document was written in order to be useful and published in the hope that it is helpful to others. There is no guarantee that this information really helps in all similar settings. Maybe things are still broken deep inside, but my little demo application at least does not choke on startup or finalization anymore. If you have additional insight, please share this information. Contact me by mail and/or followup to this post. So here is a summary of what I found out: I create a solution containing a C++/CLI project and a C# (Google: CSharp) project, which references the C++/CLI project. The C++/CLI project is a DLL-project which uses the Boost libaries. Without any further settings, the autolink features of Boost are configured such that the Boost libraries are statically linked to the C++ DLL (which IMHO normally is fine and exactly what I want: no extra libraries to ship with my software). Note that some libaries may be used implicitly: Spirit for example includes Boost.Threads when BOOST_SPIRIT_THREADSAFE is defined. Alas, the default compiler settings may lead to trouble: Statically linking to Boost libraries may yield an executable which chokes on startup with a System.BadImageFormatException, even if the compiler and linker run without warning (a bug, IMHO). Explanantion: <cite author="Anthony Williams" date="2009-02-04 15:54:40 GMT"> The problem is that the static boost thread library tries to hook the native win32 PE TLS callbacks in order to ensure that the thread-local data used by boost thread is cleaned up correctly. This is not compatible with a C++/CLI executable. </cite> Solution: In Configuration Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions add BOOST_ALL_DYN_LINK in order to force the usage of the DLLs. In addition copy the necessary DLLs to the directory where the executable resides. E.g. copy boost_thread-vc90-mt-gd-1_XX.dll to MyApp/bin/Debug. It also helps to #define BOOST_LIB_DIAGNOSTIC in the Preprocessor Definitions to find out from the compiler output which libraries are to be included. The .NET framework throws a System.IO.FileNotFoundException on missing libraries without further information about which files are missing (The classical Mirosoft way to handle these things since Windows 98: "An error has occurred.") Setting these compiler flags should yield an application that does not fail on startup. Enters the next bug of Visual Studio: The C++/CLI compiler deliberately chooses to ignore the #pragma managed(push, off) / #pragma managed(pop) PREPRO directives for files which are compiled with /clr command line flag. You obtain a plethora of warnings of the form warning C4793: 'boost::[..]::`vcall'{0}'' : function compiled as native : For the executable this means that on termination another exception is thrown, which adds to the confusion: Unhandled exception at 0x7c812a7b in XXX.exe: 0xC0020001: "Die Zeichenfolgenbindung ist unzulässig." or in english: Error 1700 "The string binding is invalid" or RPC_S_INVALID_STRING_BINDING. Solution: Put managed (CLI) and unmanaged C++ code into different compilation units. For unmanaged code files change the compiler settings this way: In "Configuration Properties -> C/C++ -> General -> Compiler with Common Language" support choose "No Common Language Support". Now things should work fine. best regards, Markus

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Re: [Boost-users] boost and std collisons in c++0x
by Daniel Lidström 10 Feb '09

10 Feb '09

_____ From: Sergey Sadovnikov [mailto:flex_ferrum@artberg.ru] Sent: Thursday, February 05, 2009 10:02 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] boost and std collisons in c++0x MF> If you want to use boost, use boost::. If you want to use the STD MF> library, use std::. Perfectly! What you can say about following pieces of code: std::vector<std::shared_ptr<SomeClass>> vec; std::for_each(vec.begin(), vec.end(), std::bind(&std::shared_ptr<SomeClass>::get, std::placeholders::_1, std::bind(&SomeClass::foo, std::placeholders::_1, 10))); and vector<shared_ptr<SomeClass>> vec; for_each(vec.begin(), vec.end(), bind(&shared_ptr<SomeClass>::get, _1, bind(&SomeClass::foo, _1, 10))); Here's what I do, for every class that's put in shared_ptr's (I'm very disciplined in this way): // SomeClassFwd.h: class SomeClass; typedef std::shared_ptr<SomeClass> SomeClassPtr; typedef std::vector<SomeClassPtr> SomeClassCollection; Now, your code becomes: SomeClassCollection vec; std::for_each(vec.begin(), vec.end(), std::bind(&SomeClassPtr::get, std::placeholders::_1, std::bind(&SomeClass::foo, std::placeholders::_1, 10))); I would agree C++ can be very verbose. Using typedef can limit this a lot though. /Daniel Lidström

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Is bimap swappable?
by Adam Badura 10 Feb '09

10 Feb '09

The documentation for Boost.Bimap does not mention that bimap is swappable (but it does not warn explicitly that it is not - which it should IMHO if it is not). When compiling the code (under VC 2008, Boost 1.38) a.swap(b) compiles for a and b being bimap of the same type. How is it then? Adam Badura

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[proto] problem with templated recursive transform
by Daniel Oberhoff 10 Feb '09

10 Feb '09

Hi, I have gotten my hands pretty dirty with my array expression DSEL, and hove gotten surprisingly far (surprisingly considering the amounts of black template magic involved :) ). Now I am stuck with a templated recursive transform, that I cant seem to get right. Here is a stripped down version: template<typename T, typename IndexSet> struct ExpressionIteratorBuilder : proto::or_< proto::when< cpudata_indexing_grammar< proto::_ > , TerminalIteratorBuilder<T, IndexSet>( proto::_ ) > ,proto::when< proto::unary_plus< cpudata_grammar > , ExpressionIteratorBuilder<T, IndexSet>( proto::_left ) > > {}; so what does work is when I have the first case (i.e. the expression is just an indexed array terminal), but the second case, where it recurses breaks on instantiation. I have tried all the tricks from the proto docs, i.e. adding a dummy callable template parameter, specializing boost::proto:::is_callable, and wrapping the recursion in proto::call, always the same long error. It also works when ExpressionIteratorBuilder is not a template, though that would not make it very useful. Any ideas? Otherwise I am beginning to love proto, and am looking forward to c++0x when the error messages might become readable through concepts :). Best Daniel -- --- Daniel Oberhoff Fraunhofer FIT Schloss Birlinghoven 53754 Sankt Augustin, Germany Tel.: +49-(0)-2241-14-3486 Fax.:+49 (0) 2241/14-2080

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Boost 1.38.0 released
by Beman Dawes 10 Feb '09

10 Feb '09

Boost 1.38.0 has been released and is available from SourceForge. See http://sourceforge.net/projects/boost/ This release includes three new libraries: Flyweight, ScopeExit, and Swap. Updated Libraries: Accumulators, Any, Asio, Config, Date_Time, Exception, Filesystem, Graph, Hash, Interprocess, Intrusive, Lexical Cast, Math, Multi-index Containers, Proto, Regex, Thread, TR1, Type Traits, Unordered, and Xpressive. Other Changes: Experimental CMake build system. You can read the full release announcement here: http://www.boost.org/users/news/version_1_38_0 The release managers were Beman Dawes, Daniel James, Eric Niebler, and Rene Rivera. --Beman Dawes

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Data_Time - Exception: could not convert calendar time to UTC time
by Bruno Dutra 09 Feb '09

09 Feb '09

Hello folks, Today I downloaded the new version of Boost, 1.38, and tried to compile and run the Source listing for Timer.5<http://www.boost.org/doc/libs/1_38_0/doc/html/boost_asio/tutorial/tuttimer5…>example from Asio, but it was throwing the exception: "could not convert calendar time to UTC time" (Note that i'm building it under windows vista using MinGW GCC, which I believe is not on the "tested compilers list of boost 1.38") After some time traking the culprit, I got to the function time_type microsec_clock::create_time(time_converter converter) from the boost\date_time\microsec_time_clock.hpp header in which the variable 'std::time_t t' was strangely assuming a negative value, probably due to an overflow. Then I realized that changing the type of the variable 'micros' from uint64_t to std::time_t on that same function, could solve the problem. I just want to know if that's a known issue and if applying that small fix other issues may appear. Thanks in advance Bruno

1 0

[Proto] implementing an computer algebra system with proto
by Kim Kuen Tang 09 Feb '09

09 Feb '09

Hi all, considering the following expression created with proto: "3 *var_+5=2; .. The tree would be : = / \ + 2 / \ * 5 / \ 3 var_ Here the term "var_" is somewhat a placeholder. I wonder wheter it is possible now to change the structure of the tree. That is i want to define a grammar that is able to produce another expression like this. "var_=(2-5)/3;" In tree: = / \ var_ div / \ - 3 / \ 2 5 With this expression i can now define a context that return the final result of the right hand side. But is this possible in proto with the existing functions? This situation is somewhat different from the examples in the documentation. Here i dont want to replace the child node. The whole structure of the input tree should be transformed in another one. Cheers Kim Tang

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boost accumulators - kth central moments? [and slow compiles]
by Gordon Anderson 09 Feb '09

09 Feb '09

I have a couple Qns about boost accumulators in 1_37_0 - 1) Central moments ? - There are accumulators for simple kth moments - boost/accumulators/statistics/moment.hpp Are central kth moments [relative to the mean] there somewhere? Obviously you can construct one from the other with a weighted sum of the k moments on the same data. 2) Slow build ! - It is a bit slow to compile code using eg. moment<6> accumulators.. It takes around 12 seconds on my machine to build sample code with 'moment<12>' exponential recursive template evaluation?? I'm using gcc 4.2.4 cheers, gord.

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Re: [Boost-users] Cycles of shared_ptr
by Donovan Parks 09 Feb '09

09 Feb '09

Hello Alan, Thanks for the response. I appreciate what you are saying and realize that we need to draw up some diagrams which indicate ownership rules. It turns out my problem was actually unrelated to cycles of shared_ptr, but it is still good to be thinking about this possibility. Cheers, Donovan

1 0

Building on OS X
by Stuart Dootson 09 Feb '09

09 Feb '09

So, I've installed Xcode 3.0, followed by Xcode 3.1.2. gcc is defaulting to 4.0, which builds Boost fine (using the configure & make install OR bjam routes). However, I would like to build boost with gcc 4.2, as installed with Xcode 3.1.2 - I've not managed to find the correct incantation yet to persuade Boost to use 4.2 vs 4.0 - help!!!! I guess I could just alter the gcc and g++ soft links in /usr/bin, but that seems...wrong. Assistance would be greatly appreciated. TIA!!! Stuart Dootson

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Re: [Boost-users] Cycles of shared_ptr
by Alan M. Carroll 09 Feb '09

09 Feb '09

Detecting cycles at run time is expensive and rarely worth the effort. It is much better to have a clear understanding of your data structure and awareness of where cycles could arise and then break them using Boost.weak_ptr, as weak_ptr was created to deal with exactly this problem. For instance, if you have a tree that needs parent to child and child to parent links, then you can use shared_ptr in the parent class and weak_ptr in the child struct. The important thing is to be clear on the ownership semantics. There are so many possibilities that it's hard to be more specific without a lot of detail. At 12:01 PM 2/9/2009, you wrote: >I have recently started using boost::shared_ptr in my code. I >understand that cycles of shared_ptr will cause a problem. Now, I >strongly believe that such a situation has arisen in my code and am >wondering if there is any advice/tips on how one can detect when a >cycles of shared_ptr has occured. The code I am working on is >developed by several people and the shared_ptr of interest is passed >to many objects.

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Cycles of shared_ptr
by Donovan Parks 09 Feb '09

09 Feb '09

Hello, I have recently started using boost::shared_ptr in my code. I understand that cycles of shared_ptr will cause a problem. Now, I strongly believe that such a situation has arisen in my code and am wondering if there is any advice/tips on how one can detect when a cycles of shared_ptr has occured. The code I am working on is developed by several people and the shared_ptr of interest is passed to many objects. Thanks for any and all help. Cheers, Donovan PS: This is my first time posting to boost-users.

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Building boost regex on Vxworks compiler
by Raghavender Boorgapally 09 Feb '09

09 Feb '09

Hi, I am assigned the job of building the boost regex on VXworks gcc compiler. >From the boost regex documentation, I see that we need to have a make file corresponding to the platform to build the library. Can some one tell me how to build it for Vxworks gcc, if they have built the library earlier.

2 1

[regex] character sets
by Detlef Meyer-Eltz 09 Feb '09

09 Feb '09

I'm working with CBuilder6 and boost boost_1_34_1 and found, that regex expression1("[[:print:]]+"); matches with regex_search the whole string: testtext = "ab\r\ncd ef"; including the linebreak and the white space. I had assumed, that the print-class would consist exactly in the set of characters for which the standard function isprint returns true but isprint returns false for the space characters. Is there there any documentation with the exact enumerations of the different character sets? With Kind Regards, Detlef Meyer-Eltz

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[Smart Ptr] make_shared for arrays
by Alexander 09 Feb '09

09 Feb '09

Why isn't there ? It looks easier to implement than for single objects as there would be only unary version which would take array size.

1 0

boost serialization not working unless you have at least one virtual function in base
by Martin Seiler 09 Feb '09

09 Feb '09

Hi all, Does anybody know why this is the case? Is there a way to make a class "polymorphic" without adding a dummy virtual function? Is this some "silly" optimization done by C++ compilers? Not generating vtables? It took me quite some time to figure this one out. It is mentioned in the documentation (2 lines, easily missed). http://www.boost.org/doc/libs/1_37_0/libs/serialization/doc/serialization.h… Maybe add a big huge WARNING? Also please mention this fact in the examples! (like in demo.cpp?) regards M. Seiler #include <boost/archive/xml_oarchive.hpp> #include <boost/archive/xml_iarchive.hpp> #include <boost/serialization/nvp.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/type_info_implementation.hpp> #include <boost/serialization/export.hpp> #include <boost/archive/archive_exception.hpp> #include <boost/archive/basic_xml_archive.hpp> class A { public: A() : test(33) { } int test; virtual void dummy(){} // if you comment this line it won't work }; class B : public A { public: B() : test_b(52) { } int test_b; virtual void foo(){}; }; namespace boost { namespace serialization { template<class Archive> void serialize(Archive & ar, A & o, const unsigned int version) { ar & make_nvp("test", o.test); } template<class Archive> void serialize(Archive & ar, B & o, const unsigned int version) { ar & boost::serialization::make_nvp("A", boost::serialization::base_object<A>(o)); ar & make_nvp("test_b", o.test_b); } } } BOOST_CLASS_EXPORT(B); // Should register B for all archives such that it can be serialized of the basepointers void main() { A* a = new B(); boost::archive::xml_oarchive archive(std::cout); archive.template register_type<B>(); // Should register B for this archive archive & boost::serialization::make_nvp ("a", a); // If you check the output, you see that `{B}.test_b' was not serialized int i; std::cin >> i; }

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Need boost_regex_vc7_mssd.lib
by Dyuti Barma 09 Feb '09

09 Feb '09

Hi, I'm not sure where to find boost_regex_vc7_mssd.lib and the corresponding library for VC8. Can anyone let me know where to get the above libs from ? Thanks Dyuti

2 1

Boost.lambda: how to sort this vector with function?
by Joost Kraaijeveld 09 Feb '09

09 Feb '09

I want to sort a vector of Edges according to their remaining estimated distance to the finish point (an own implementation of a graph algorithm). How do I sort this vector with edges: // Returns the cost between start and finish, given a graph int CostEstimate( const Graph& aGraph, const Vertex& start, const Vertex& finish) ... // Member function of a graph std::vector< Edge > v = ...; // Sort them according to the cost std::sort( v.begin(), v.end(), boost::lambda::bind( CostEstimate( (*this), boost::lambda::bind( &Edge::otherSide, &start, boost::lambda::_1), finish)) < boost::lambda::bind( CostEstimate( (*this), boost::lambda::bind( &Edge::otherSide, &start, boost::lambda::_2), finish))); where otherSide is a const function of the class Edge which returns a "const Vertex&" Compiling this results in an error: error: invalid initialization of reference of type ‘const Vertex&’ from expression of type ‘const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::action<3, boost::lambda::function_action<3, boost::lambda::detail::unspecified> >, boost::tuples::tuple<const Vertex& (Edge::* const)(const Vertex&)const, const Vertex* const, const boost::lambda::lambda_functor<boost::lambda::placeholder<1> >, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type> > >’ TIA -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 web: www.askesis.nl

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[Graph] is it possible to define my own edge_descriptor
by George Slavov 09 Feb '09

09 Feb '09

Hello, I have a graph which corresponds to an n by m grid of vertices. Edges in this graph are only allowed to point from one vertex to an adjacent vertex. In this situation, it would be wonderful if I could define an edge, so that its target is not a vertex_descriptor but some other construct which would allow me to store the target in just one byte or less instead of the full unsigned int which I use to describe my vertices. That is, the edge could go from vertex 102 to a descriptor in the range [0,8] which would give you enough information to compute which vertex you're talking about. The graph I'm working with is rather large. It could have millions of vertices and saving this kind of space would be fantastic. If it's important at all, mostly I'll be doing topological sort on these graphs. Is this possible? Best, George Slavov

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NURBS curves/surfaces
by Peter Barker 09 Feb '09

09 Feb '09

Hello, Is there anything in Boost current or planned to deal with NURBS curves/surfaces? Regards, Pete

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[boost-users][asio] why boost::thread thread1(boost::bind(...)) doesn't start io_service on multicore machine?
by tomasz jankowski 09 Feb '09

09 Feb '09

I would like to test my class which implements shared data. because of it I have written test code which use boost::thread & boost asio (please see below). the problem is that threads are NOT started... on multicore machine. one one core machine it runs fine. any idea why? tom #include <iostream> #include <istream> #include <ostream> #include <string> #include <boost/asio.hpp> #include <boost/date_time/posix_time/posix_time.hpp> #include <boost/bind.hpp> #include <boost/thread.hpp> #include "shared.hpp" #include <boost/random/linear_congruential.hpp> #include <boost/random/uniform_real.hpp> #include <boost/random/variate_generator.hpp> SharedData replyToClients; void handle_timeout1(const boost::system::error_code&) { boost::minstd_rand generator(42u); boost::uniform_real<> uni_dist(0,1); boost::variate_generator<boost::minstd_rand, boost::uniform_real<> >uni(generator, uni_dist); std::string key = "ello";std::cout<<key<<std::endl; std::string value1 = "see you later aligator"; std::string value2 = "what do you want to eat today?"; double cond = 0.500000; while(true){ if(uni() >= cond){ replyToClients.set(key,value1); }else{ replyToClients.set(key,value2); } } } void handle_timeout2(const boost::system::error_code&) { std::string key = "ello"; while(true){ std::cout<<replyToClients.get(key); } } int main(int argc, char* argv[]) { try{ boost::asio::io_service io_service; boost::system::error_code error; //boost::asio::io_service::work work(io_service); io_service.post(boost::bind(handle_timeout1,error)); io_service.post(boost::bind(handle_timeout2,error)); io_service.post(boost::bind(handle_timeout2,error)); io_service.post(boost::bind(handle_timeout2,error)); boost::thread thread1(boost::bind(&boost::asio::io_service::run, &io_service)); boost::thread thread2(boost::bind(&boost::asio::io_service::run, &io_service)); boost::thread thread3(boost::bind(&boost::asio::io_service::run, &io_service)); boost::thread thread4(boost::bind(&boost::asio::io_service::run, &io_service)); //io_service.run(); std::cout<<"the end\n"; io_service.stop(); thread1.join(); thread2.join(); thread3.join(); thread4.join(); } catch (boost::system::system_error& er) {std::cout << "Exception er: " << er.what() << "\n"; } catch (std::exception& e) { std::cout << "Exception e: " << e.what() << "\n"; } return 0; } ---------------------------------------------------- Nużą Cię utarte scenariusze? Wymyśl własną grę flashową i wygraj główną nagrodę 5.500 Euro: http://klik.wp.pl/?adr=http%3A%2F%2Fwhosegame.pl%2Fcontestcard.php%3Fcontes…

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[program_options] VM object unable to store the values of options
by Wenjing Jia 09 Feb '09

09 Feb '09

(Apologies if this message has come out for more than once, as I had problem with authorization and is unsure when the message is able to be seen by boost users!) Hi, I'm met a very weird thing when using the “Boost.Program_options” library. Somehow, the variable-map(VM) object is unable to store values of options which are fed in from the command line. I've been stuck in this stupid problem for two days and cannot find any clue about it. Can someone please give me a hint? I'm using the Visual Studio 2005 on Windows XP SP3 to compile some examples provided in Boost.Program_options Tutorial. The boost library was installed using the boost_1_34_1 installer. However, no matter what value I input to any option, the variable-map object "vm" I defined is unable to store it and output it correctly. For instance, I followed the instructions in the Tutorial of the Boost.Program_options and compiled the first simplest possible example "example/first.cpp". I then went to "start" of Windows XP and Run "cmd", then run: "first --compression 10". The output is always "Compression level was set to -858993460." regardless of what value I type after the "--compression". Below is the full codes of the program (copied from the "example/first.cpp"): ------------------------------------------------------------------------------- #include <boost/program_options.hpp> namespace po = boost::program_options; #include <iostream> #include <iterator> using namespace std; int main(int ac, char* av[]) { try { po::options_description desc("Allowed options"); desc.add_options() ("help", "produce help message") ("compression", po::value<int>(), "set compression level") ; po::variables_map vm; po::store(po::parse_command_line(ac, av, desc), vm); po::notify(vm); if (vm.count("help")) { cout << desc << "\n"; return 1; } if (vm.count("compression")) { cout << "Compression level was set to " << vm["compression"].as<int>() << ".\n"; } else { cout << "Compression level was not set.\n"; } } catch(exception& e) { cerr << "error: " << e.what() << "\n"; return 1; } catch(...) { cerr << "Exception of unknown type!\n"; } return 0; } ------------------------------------------------------------------------------- I also tried on the other examples mentioned on that web page, such as "example/options_description.cpp". When I type: "options_description --optimization 4 -I foo a.cpp", the output is: "Include paths are: Input files are: Optimization level is -858993460". That is the input values are not taken and stored by the vm object. Why such a simple example won't work on my machine!? Your suggestion would be most appreciated! Many thanks in advance! Wenjing

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boost graph compiling problem with vc7.1
by liulewes 08 Feb '09

08 Feb '09

Dear there: I recently started to use the boost graph library and I got the following problem. I'v 2 projects A and B in my vc 7.1 solution. A uses boost graph lib while B is dependent on A. I'v no problem compiling A but got some errors in B like this: C:\Program Files\boost\boost_1_35_0\boost\graph\detail\adjacency_list.hpp(2292): error C2039: 'size_type' : is not a member of 'boost::vec_adj_list_impl<Graph,Config,Base>' with [ Graph=boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>, Config=boost::detail::adj_list_gen<boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>,boost::vecS,boost::vecS,boost::undirectedS,boost::detail::retag_property_list<boost::vertex_bundle_t,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>>::type,boost::detail::retag_property_list<boost::edge_bundle_t,boost::property<boost::edge_weight_t,double>>::type,boost::no_property,boost::listS>::config, Base=boost::detail::adj_list_gen<boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>,boost::vecS,boost::vecS,boost::undirectedS,boost::detail::retag_property_list<boost::vertex_bundle_t,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>>::type,boost::detail::retag_property_list<boost::edge_bundle_t,boost::property<boost::edge_weight_t,double>>::type,boost::no_property,boost::listS>::DirectedHelper ] and even like this: C:\Program Files\boost\boost_1_35_0\boost\pending\container_traits.hpp(150): error C2065: 'list' : undeclared identifier I think that I have all the standard headers included. Where mush I have been wrong? Thanks _________________________________________________________________ MSN资讯快递，帮助你第一时间了解最新资讯！ http://im.live.cn/newsexpress

2 1

Linking boost in iphone application
by Gustavo Garcia Bernardo 08 Feb '09

08 Feb '09

Hi, After building boost for the iphone following these instructions http://lists.boost.org/boost-users/2008/11/42094.php , I have a problem using it in my iphone application. If I link any part of boost with the application it crashes at startup. I don't have any problem linking other C++ library. Has anybody else faced the same problem? How to reproduce it: 1. Create a objective-c class in the application (Test.h, Test.mm) 2. Include "#import <boost/system/error_code.hpp>" in the Test.mm file. 3. Link libboost_system-xgcc40-mt_1.37.a Thank you very much for any clue, G.

1 0

string iterator not dereferencable
by Alessandro Condotta 07 Feb '09

07 Feb '09

Hi all, I am newbie and I am developing in C++ using VC9, Boost 1.37, CPLEX 11.1. I use date_time and program_options boost libraries and my program compiles fine. Date_time works perfectly while program_options gives me a runtime error saying "Debug assertion failed .... string iterator not dereferencable" every time I pass any argument in the command line. The assertion fails at line 112 of "C:\program files\microsoft visual studio 9.0\vc\include\xstring" So I try to figure out what was going on in the following way: - I tried "first.cpp" in program option example directory on a new project: it works with no problem. -Then I tried to replace the main function of my project with the exact code of "first.ccp" and I got "string iterator not dereferencable" again. Can anyone help me ? Many thanks in advance Alessandro

4 4

[thread_pool|range_ex|bind] Extrange behaviour with fibonacci example and parallel_sort
by vicente.botet 07 Feb '09

07 Feb '09

Hi, I have tried to do a parallel_sort using the Boost.ThreadPool library and I get some realy extrange. I have copied the fibonacci example and adapted it to do a parallel sort. See attached file. When I set the defines FIBO this works some times, don't finish others and crash the others. I have added some traces (define COUT) and I get better results but not always correct. I suspected that the threads in the thread pool needs to be stoped. I have added a pool shutdown but nothing changes. Oliver, could you take a look? When I define X_SORT the compilation even do not finish. What is wrong on my definition of parallel_sort? Am I using boost:bind incorrectly? Is there some issue with binding function templates? Can some one help me? Thanks in advance, Vicente P.S. I'm using Boost 1.37 + The file compiles only with the lates version of the Boost.Range library http://www.boostpro.com/vault/index.php?action=downloadfile&filename=range_… and the Boost.ThreadPool version 17 http://www.boostpro.com/vault/index.php?action=downloadfile&filename=boost-… $ gcc --version gcc (GCC) 3.4.4 (cygming special, gdc 0.12, using dmd 0.125) 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. Debug session $ gdb x_sort2 GNU gdb 6.8.0.20080328-cvs (cygwin-special) Copyright (C) 2008 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i686-pc-cygwin"... (gdb) help List of classes of commands: aliases -- Aliases of other commands breakpoints -- Making program stop at certain points data -- Examining data files -- Specifying and examining files internals -- Maintenance commands obscure -- Obscure features running -- Running the program stack -- Examining the stack status -- Status inquiries support -- Support facilities tracepoints -- Tracing of program execution without stopping the program user-defined -- User-defined commands Type "help" followed by a class name for a list of commands in that class. Type "help all" for the list of all commands. Type "help" followed by command name for full documentation. Type "apropos word" to search for commands related to "word". Command name abbreviations are allowed if unambiguous. (gdb) run Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 3056.0x128] [New thread 3056.0x68c] std::sort: reverse 0..100000 0.05 s [New thread 3056.0xfe4] [New thread 3056.0x1c8] 55 Program exited normally. (gdb) run Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 4028.0xd48] [New thread 4028.0xef4] std::sort: reverse 0..100000 0.03 s [New thread 4028.0x9ec] [New thread 4028.0x5bc] [New thread 4028.0x3bc] [Switching to thread 4028.0x3bc] Quit (gdb) run The program being debugged has been started already. Start it from the beginning? (y or n) y Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 2220.0x4dc] [New thread 2220.0xe58] std::sort: reverse 0..100000 0.05 s [New thread 2220.0x9b0] [New thread 2220.0x778] [New thread 2220.0x264] Program received signal SIGINT, Interrupt. [Switching to thread 2220.0x264] 0x7c87635d in KERNEL32!GetConsoleCharType (Quit (gdb) run The program being debugged has been started already. Start it from the beginning? (y or n) y Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 3964.0xf40] [New thread 3964.0xedc] std::sort: reverse 0..100000 0.05 s [New thread 3964.0x320] [New thread 3964.0xe44] [New thread 3964.0x544] [Switching to thread 3964.0x544] Quit (gdb) q The program is running. Exit anyway? (y or n) y Vicente@viboes1 ~/SVN/bin.v2/vbe_interthreads/libs/interthreads/test/x_sort2.tes t/gcc-3.4.4/debug/link-static/threading-multi $ gdb x_sort2 GNU gdb 6.8.0.20080328-cvs (cygwin-special) Copyright (C) 2008 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "i686-pc-cygwin"... (gdb) run Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 1076.0x31c] [New thread 1076.0x9b8] std::sort: reverse 0..100000 0.05 s [New thread 1076.0xaec] [New thread 1076.0xdc0] 19239 [unknown (0xDC0)] x_sort2 1076 _cygtls::handle_exceptions: Exception: ST ATUS_ACCESS_VIOLATION 59227 [unknown (0xDC0)] x_sort2 1076 open_stackdumpfile: Dumping stack trace t o x_sort2.exe.stackdump Program received signal SIGSEGV, Segmentation fault. [Switching to thread 1076.0xdc0] 0x610b6132 in pthread_cond::~pthread_cond () from /usr/bin/cygwin1.dll (gdb) run The program being debugged has been started already. Start it from the beginning? (y or n) y Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 1876.0x8dc] [New thread 1876.0x938] std::sort: reverse 0..100000 0.05 s [New thread 1876.0x624] [New thread 1876.0xe28] 55 Program exited normally. (gdb) run Starting program: /home/Vicente/SVN/bin.v2/vbe_interthreads/libs/interthreads/te st/x_sort2.test/gcc-3.4.4/debug/link-static/threading-multi/x_sort2.exe [New thread 3240.0xef8] [New thread 3240.0xfb8] std::sort: reverse 0..100000 0.05 s [New thread 3240.0x5d4] [New thread 3240.0xe04] [New thread 3240.0x884] [Switching to thread 3240.0x884] Quit (gdb) q The program is running. Exit anyway? (y or n) y

1 0

Re: [Boost-users] Welcome to the "Boost-users" mailing list
by liulewes 07 Feb '09

07 Feb '09

Dear there: I recently started to use the boost graph library and I got the following problem. I'v 2 projects A and B in my vc 7.1 solution. A uses boost graph lib while B is dependent on A. I'v no problem compiling A but got some errors in B like this: C:\Program Files\boost\boost_1_35_0\boost\graph\detail\adjacency_list.hpp(2292): error C2039: 'size_type' : is not a member of 'boost::vec_adj_list_impl<Graph,Config,Base>' with [ Graph=boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>, Config=boost::detail::adj_list_gen<boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>,boost::vecS,boost::vecS,boost::undirectedS,boost::detail::retag_property_list<boost::vertex_bundle_t,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>>::type,boost::detail::retag_property_list<boost::edge_bundle_t,boost::property<boost::edge_weight_t,double>>::type,boost::no_property,boost::listS>::config, Base=boost::detail::adj_list_gen<boost::adjacency_list<boost::vecS,boost::vecS,boost::undirectedS,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>,boost::property<boost::edge_weight_t,double>>,boost::vecS,boost::vecS,boost::undirectedS,boost::detail::retag_property_list<boost::vertex_bundle_t,boost::property<vmap_id_t,int,boost::property<boost::vertex_color_t,RGBColor,boost::property<vertex_feature_t,FeatureVector2D<double> *>>>>::type,boost::detail::retag_property_list<boost::edge_bundle_t,boost::property<boost::edge_weight_t,double>>::type,boost::no_property,boost::listS>::DirectedHelper ] and even like this: C:\Program Files\boost\boost_1_35_0\boost\pending\container_traits.hpp(150): error C2065: 'list' : undeclared identifier I think that I have all the standard headers included. Where mush I have been wrong? Thanks. _________________________________________________________________ MSN热搜榜，每天最In的信息资讯和热点排行让您一览无余！ http://top.msn.com.cn

2 1

[date_time] Timer anomolies on Windows
by Rush Manbert 07 Feb '09

07 Feb '09

I am trying to implement an accurate cross-platform timer with microsecond resolution. I would like to use the Boost date_time library to replace our current platform-specific code. One reason to do this is because we currently use the Code Audio framework timing services on the Mac and we would like to get away from that. In general, we want to statically link our executables. The current implementation uses the Core Audio framework on the Mac and the QueryPerformanceCounter() API on Windows. Our experience with the Windows code is that it doesn't perform well when measuring any interval less that about 500 msec. I have written a number of tests that get the number of performance counter ticks over various intervals. One test uses the GetTickCount() millisecond timer to measure the intervals. Another test just uses a for loop that increments a variable, because I was suspicious that the millisecond timer was jittery. I have found that the QueryPerformanceCounter() results are unreliable. One test ran tests of durations from 100 msec to 2000 msec and calculated the error between the number of ticks reported and the counter frequence returned by the API QueryPerformanceFrequency call. After getting that result, I wrote the same test that counts boost::posix_time::microsec_clock::local_time() ticks against the millisecond clock. I was initially surprised to see that the error between the counts reported by the API calls and the 1 megahertz expected frequency are nearly identical to the errors I calculated for QueryPerformanceCounter(). This led me to believe that the date_time microsec_clock implementation must be using the QueryPerformanceCounter interface. I have searched the sources, however, and I don't find anything that is Windows-specific. One other odd thing that my tests reveal. If I run a test that times its duration using the GetTickCount() millisecond timer, and calls either QueryPerformanceCounter() or uses microsec_clock to get the number of ticks seen during the interval I find that the values returned by QueryPerformanceCounter() are different for each test duration, as one would expect. Conversely, the tick counts calculated for microsec_clock are identical (with the value 15625) for 1 msec through 16msec. Then at 17 msec test duration, the tick count jumps to 31250. The same count gets reported through durations of 31 msec. At 32 msec the count jumps to 46875 and remains there through a test duration of 47 msec... This looks like the Boost microsec_clock tick count is only updating at 60 Hz. Obviously, I am very bewildered by these results. I would really appreciate it if anyone can enlighten me on the following: 1) On Windows, what API is actually being used to read the clock ticks? 2) Where is the platform-specific code that date_time uses to actually read the counters? 3) Is there really a 60 Hz update to the microsec_clock count value? Here is an example of one of my tests. This one is for the QueryPerformanceCounter() API. The Boost microsec_clock test is nearly identical: int WindowsPerformanceTimerResolutionSubTest (unsigned int testDurationInMillisecs) { LARGE_INTEGER startHighRes; LARGE_INTEGER endHighRes; DWORD start; if (0 == testDurationInMillisecs) { testDurationInMillisecs = 1; } // Sync to clock edge using GetTickCount() windowsSyncToClockEdgeOneMillisecond (); // Get our start time for the performance clock, and the millisecond clock QueryPerformanceCounter (&startHighRes); start = GetTickCount(); // Wait for the required duration while ((GetTickCount() - start) < testDurationInMillisecs) { // Nothing to do } //Get the microsec time at end of test QueryPerformanceCounter (&endHighRes); // Difference divided by number of seconds is ticks per second uint64_t diffTicks = endHighRes.QuadPart - startHighRes.QuadPart; return diffTicks; } Thanks, Rush

1 0

[intrusive] first impression and constant-time removal
by Erik Cassel 07 Feb '09

07 Feb '09

Hello, I like the intrusive library. I'm refactoring my code to use it in many places. One of the benefits of boost::intrusive is the constant-time removal of items from a collection. The documentation doesn't tell you how to remove an element from a list in constant time, so I looked through the API. At first, "remove" looked like a good idea, but this function removes all instances that match a given value - so it is O(n). The unwary programmer will inadvertently use this function, not realizing the huge waste of CPU time. >From what I can tell, the way to remove an element in constant time is this: if (element.is_linked()) list.remove(list.iterator_to(element)); It requires 3 function calls. How about adding the something like the following function to list? void remove_member(reference value) It might follow the same pattern as std::set's erase, which returns the erasure count (0 or 1) as a size_t. Summary: 1) I found the remove() function's name ambiguous. It isn't clear that the complexity is linear time - that it compares elements to a value rather than taking a reference to an actual element. The only hint is the const_reference (rather than a reference) argument. Would "remove_all_matches" would be a better name? 2) Removing an element from a list requires 3 function calls. Wouldn't an std::set-style erase(reference) be a good addition to the API? It could be called "remove_member" or simply "erase". 3) If nothing else, it might be wise to have a small section in the documentation that demonstrates constant-time element removal and warns against improper use of "remove". -Erik

3 7

Compilation problem with 1.37.0 on OS X
by Stephen Blinkhorn 07 Feb '09

07 Feb '09

Hello Boost people, I have problems compiling a project after upgrading to Boost 1.37.0 from an earlier version, dating back to July 08 ish. This is on Mac OS X 10.5.6, XCode 3.1 etc. Swapping back to my older Boost install resolves all problems. Errors: Precompiling /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/ AppKit.framework/Headers/AppKit.h powerpc-apple-darwin9-gcc-4.0.1: installation problem, cannot exec '/ Developer/usr/bin/../libexec/gcc/powerpc-apple-darwin9/4.0.1/cc1obj': Argument list too long I don't understand why this causes problems, happens on two different machines after reinstalling GCC etc. Curious. Stephen

2 1

Problem with Iterator passing inside an index... a little complex...
by Rodrigo Dias Ferreira 06 Feb '09

06 Feb '09

Hi There, I am using the Boost.MultiIndex and I am facing a problem that I am try to resolving (debbuging) already about 20 hours... I think I get the problem isolated, but I don't know how to solve, and I don't know if this it is implemented. So I decided to make a example, it is a little big, but I put it as resumed as I could and post here in order to know if anyone could help me out. I will try to explain briefly here, I will copy the main() code right under the explanation, but the whole code of the example is in the end of the e-mail (with the classes and functions) If you want you could try to run too see what is the problem that I am talking about.) When I try to access an pair of iterators pair<propIt,propIt> that I stored inside a class (propertystream_h), somehow is changing to where the iterator points, I think it could be because the object which has originate (Graph) the index is created, stored in in a static index (which I call _graphRep) from the DynamicGraphs, passed to a handler (Graph_h), and then after the Graph goes out of scope it is destroyed. When the Graph_h._localGraph (copy of the iterator->Graph returned by the insertion in the _graphRep) access its member _globalProperties (which is an index containing the fields: {string _key, string _value, propertystream_h _props} from the struct globalPropSchema) through a iterator (let's call it: gpit), then it is fine. But then when I try to access through the gpit->_props._propRangeIt.first, the iterator of the propertystream_h (_propRangeIt.first), then the iterators, some how are messed up. ( -> in this example it points to last element, and then when I get next, never finds the end(). (sometimes it return some trash, sometimes I get segmentation fault). So I would like to know why it is messing with the iterator? And how could I solve this problem? that's it, best regards, Rodrigo P.S.: I hope someone can help me... copy of the main(): int main(){ DynamicGraphs dg; Graph_h graph_h; propertystream_h propS; property_h prop_h; GlobalPropIterator gpit; GlobalProp_h gp_h; propertystream_h ps_h; property_h p_h; graph_h = dg.createGraph("COI:0351-123-4555"); if (!graph_h) cout << "Unsuccessful creation!"<<endl; else cout << "Successful creation!" <<endl; //It works, because it takes from the _localPropRep, and it passes it as value!!! ps_h = graph_h->lookupLocalProp("name"); while(!ps_h.end()){ cout << "LocalProperties: "; p_h=ps_h.next(); cout << "Key: " << p_h.key() << " Value: " << p_h.value() <<endl; } // It does not work, because is accessing the propertystream_h from // the _globalPropRep (index of the tuple // {string globalkey, string value, propertystream_h props} // the propertystream_h it has as member a pair of iterators for another index. // -> after a lot of debugging (about 16h) OI found out that // it seems that during the creation of a graph, // when it passes the graph to graph_h, and goes out of scope, it keep the // iterator reference to the first element, but just that... the next // gives me segmentation fault. Anyone knows how to pass the graph and the its members // the indexes-repositories as value, so it would not depend on the pointing to // the graph that was freed from the memory? gpit = graph_h->properties("*"); if (!gpit) cout << "Not found any property in the globalProperties Repository."<<endl; else{ int i=0; while (!gpit.end()) { gp_h = gpit.next(); cout << "While_1::Iteration_" << ++i << endl; cout << "GlobalProperty key: " << gp_h.key() << endl; cout << "GlobalProperty value: " << gp_h.value() << endl; ps_h = gp_h.propertyStreamHandler(); int j = 0; while (!ps_h.end()){ p_h = ps_h.next(); cout << "While_2::Iteration" << ++j << endl; cout << "GlobalProperty::PropertyStream: key " << p_h.key() << endl; cout << "GlobalProperty::PropertyStream: value " << p_h.value() << endl; } } } } Here it is the code: /* * IndexProblem.cpp * * Created on: Feb 6, 2009 * Author: rodrigo */ #include <boost/multi_index_container.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/composite_key.hpp> #include <boost/tuple/tuple.hpp> #include <boost/tokenizer.hpp> #include <boost/lambda/lambda.hpp> #include <climits> #include <iomanip> #include <iostream> #include <ctime> #include <string> #if !defined(NDEBUG) #define BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING #define BOOST_MULTI_INDEX_ENABLE_SAFE_MODE #endif using std::string; using std::pair; using std::ostream; using std::cout; using std::endl; using boost::multi_index_container; using namespace boost::multi_index; struct property { string _key; string _value; /// Default Constructor property(){} /// Constructor with parameters: initialize the name and graph property(string key, string value) : _key(key), _value(value) {} /// Copy Contructor property(const property &pm) : _key(pm._key), _value(pm._value) {} //For debugging TODO: delete later friend ostream& operator<<(ostream& os, const property &p){ os << "Key: " << p._key << " value: " << p._value << endl; return os; } }; /// Indexing in the data structure PropMap typedef multi_index_container< property, indexed_by< hashed_non_unique< BOOST_MULTI_INDEX_MEMBER(property, string, _key) > > > propIndex; typedef propIndex::iterator propIt; class property_h { private: /// Access to properties through the iterator propIt _pit; public: /// Default Constructor property_h(){} /// Constructor with Parameters: for lookup of Nodes property_h (const propIt &it) : _pit(it){} /// Constructor with Parameters: for lookup of Nodes property_h (const property_h &h) : _pit(h._pit){} /// Returns the key from the property being handled string key() const {return _pit->_key;} /// Returns the value from the property being handled string value() const {return _pit->_value;} }; class propertystream_h { /// _propRangeIt: for keeping a range in order to iterate over the graphs pair<propIt,propIt> _propRangeIt; /// _noMatches: true if there are no matches during the lookup function bool _noMatches; public: /// Default Constructor propertystream_h() : _noMatches(true){} /// Constructor with parameters for local lookup propertystream_h(pair<propIt,propIt> rangeIt, bool noMatches) : _propRangeIt(rangeIt), _noMatches(noMatches){ } /// Default Constructor propertystream_h(const propertystream_h &ps) : _propRangeIt(ps._propRangeIt), _noMatches(ps._noMatches){} // returns null_h on end of stream ... property_h next(){ return property_h(_propRangeIt.first++); } /// This function returns true whenever is the end of the stream bool end(){ return (_propRangeIt.first == _propRangeIt.second); } /// Overload operator!: shows if a creation was unsuccessful bool operator!(){ return _noMatches; } }; struct globalPropSchema{ string _key; string _value; propertystream_h _props; /// Default Constructor globalPropSchema() : _key(""), _value(""), _props(){} /// Parameter Constructor globalPropSchema(string k, string value, propertystream_h props) : _key(k), _value(value), _props(props){} /// Copy Constructor globalPropSchema(const globalPropSchema &gps) : _key(gps._key), _value(gps._value), _props(gps._props){} //TODO: Delete it: Debug friend ostream& operator<<(ostream &os, const globalPropSchema &gps){ os << "Key: " << gps._key << " Value: "<< gps._value << " PropertyStreamAdress: " << &gps._props <<endl; return os; } }; typedef multi_index_container< globalPropSchema, indexed_by< ordered_non_unique< composite_key< globalPropSchema, BOOST_MULTI_INDEX_MEMBER(globalPropSchema, string, _key), BOOST_MULTI_INDEX_MEMBER(globalPropSchema, string, _value) >, composite_key_compare< std::greater<string>, std::less<string> > > > > grobalProperties; /// Iterator for the data structure of the global properties index typedef grobalProperties::iterator globalPropIt; class GlobalProp_h{ private: /// Access to globalPropertiest items through the iterator globalPropIt _gpit; public: /// Default Constructor GlobalProp_h(){} /// Constructor with Parameters: for lookup of Nodes GlobalProp_h (const globalPropIt &it) : _gpit(it){} /// Copy Constructor GlobalProp_h (const GlobalProp_h &gph) : _gpit(gph._gpit){} /// Access to key of globalPropeties items string key(){ return _gpit->_key;} /// Access to value of globalPropeties items string value(){return _gpit->_value;} propertystream_h propertyStreamHandler(){ return _gpit->_props; } }; /// Iterator for the data structure of the global properties index typedef grobalProperties::iterator globalPropIt; class GlobalPropIterator{ private: /// _propRangeIt: for keeping a range in order to iterate over the graphs pair<globalPropIt,globalPropIt> _globalPropRangeIt; /// _noMatches: true if there are no matches during the lookup function bool _noMatches; public: /// Default Constructor GlobalPropIterator(){} /// Constructor with parameters for local lookup GlobalPropIterator(pair<globalPropIt,globalPropIt> rangeIt, bool noMatches) : _globalPropRangeIt(rangeIt), _noMatches(noMatches){} /// Default Constructor GlobalPropIterator(const GlobalPropIterator &gpi) : _globalPropRangeIt(gpi._globalPropRangeIt), _noMatches(gpi._noMatches){} // returns null_h on end of stream ... GlobalProp_h next(){ return GlobalProp_h(_globalPropRangeIt.first++); } /// This function returns true whenever is the end of the stream bool end(){ return (_globalPropRangeIt.first == _globalPropRangeIt.second); } /// Overload operator!: shows if a creation was unsuccessful bool operator!(){ return _noMatches; } }; class Graph { private: propIndex _localPropRep; /// Repository for the properties of the global properties related to the graph; grobalProperties _globalPropRep; public: // TODO: Really constructors /// Default Constructor Graph() {} /// Copy constructors Graph(const Graph &g) : _localPropRep(g._localPropRep), _globalPropRep(g._globalPropRep){} bool addProperty(string key, string value); GlobalPropIterator properties(string pattern) const; /// Function to lookup Local Properties propertystream_h lookupLocalProp(string pattern); friend class Graph_h; }; /// GraphMap: Data Structure for setting an index in the uniqueGraphName and retrieving handler Graph_h struct graphMap { string _name; Graph _graph; /// Default Constructor graphMap(){} /// Constructor with parameters: initialize the name and graph graphMap(string uniqueGraphName, Graph graph) : _name(uniqueGraphName), _graph (graph) {} /// Constructor with parameters: initialize the name and graph graphMap(const graphMap &gm) : _name(gm._name), _graph (gm._graph) {} }; ///ordered_unique Index in the data structure graph_hm typedef multi_index_container< graphMap, indexed_by< ordered_unique< BOOST_MULTI_INDEX_MEMBER(graphMap,string,_name) > > > graphIndex; /// Defing an iterator for the graphMapIndex typedef graphIndex::iterator graphIt; class Graph_h { private: /// \brief GraphIterator: Iterator pointing to the Graph graphIt _git; Graph _localGraph; bool _createSuccess; public: /// Default Constructor Graph_h() : _createSuccess(false) {} /// Constructor with Parameters: for creation of Graphs Graph_h ( pair<graphIt,bool> creation) : _git(creation.first), _createSuccess(creation.second){ _localGraph = creation.first->_graph; } /// Constructor with Parameters: for lookup of Graphs Graph_h (const graphIt &it) : _git(it), _createSuccess(false){ _localGraph = it->_graph; } /// Constructor with Parameters: for lookup of Graphs Graph_h (const Graph_h &h) : _git(h._git), _localGraph(h._localGraph), _createSuccess(h._createSuccess){} bool operator!(){ return !_createSuccess; } /// Operator-> overloading: allows access to graph members Graph* operator->() {return &_localGraph;} }; propertystream_h Graph::lookupLocalProp(string pattern){ pair<propIt,propIt> rangeIt; propIt rangeItfirst = _localPropRep.find(pattern); rangeIt.first = rangeItfirst; rangeIt.second = _localPropRep.end(); if (rangeIt.first != _localPropRep.end()) // second parameter means that the variable noMatches, so false in case that found the key return propertystream_h(rangeIt, false); else //No matches return propertystream_h(rangeIt, true); } GlobalPropIterator Graph::properties(string pattern) const{ pair<globalPropIt,globalPropIt> globalRangePropIt; bool noMatchesTmp=false; //Whole range if (!pattern.compare("*")){ globalRangePropIt.first = _globalPropRep.begin(); globalRangePropIt.second = _globalPropRep.end(); } if (globalRangePropIt.first == globalRangePropIt.second) noMatchesTmp = true; return GlobalPropIterator(globalRangePropIt, noMatchesTmp); } bool Graph::addProperty(string key, string value){ bool boolLocal, boolGlobal; pair <propIt,propIt> rangePropIt; string globalKey = "graph:"; globalKey.append(key); // "graph:namePorperty" boolLocal = _localPropRep.insert(property(key,value)).second; //Defining the whole range for iterate over the local properties rangePropIt.first = _localPropRep.begin(); rangePropIt.second = _localPropRep.end(); //Debug propIt it = rangePropIt.first; cout << "How it should be showed when accessing the iterator..."<<endl; while (rangePropIt.first != rangePropIt.second){ cout << "DEBUG@addProperty: " << *(rangePropIt.first++); } cout << endl; rangePropIt.first = it; //Debug boolGlobal = _globalPropRep.insert( globalPropSchema( globalKey, value, propertystream_h(rangePropIt, false) ) ).second; return (boolLocal && boolGlobal); } class DynamicGraphs { public: /// Data member to represent the graph repository (using ordered_unique index) static graphIndex _graphRep; Graph_h createGraph(string uniqueGraphName); }; graphIndex DynamicGraphs::_graphRep; /// Creation of Graph in DynamicGraphs Graph_h DynamicGraphs::createGraph(string uniqueGraphName){ Graph g; g.addProperty("name", uniqueGraphName); //Test g.addProperty("age", "Unknown"); g.addProperty("color", "blue"); return Graph_h( _graphRep.insert( graphMap( uniqueGraphName, g ) ) ); } int main(){ DynamicGraphs dg; Graph_h graph_h; propertystream_h propS; property_h prop_h; GlobalPropIterator gpit; GlobalProp_h gp_h; propertystream_h ps_h; property_h p_h; graph_h = dg.createGraph("COI:0351-123-4555"); if (!graph_h) cout << "Unsuccessful creation!"<<endl; else cout << "Successful creation!" <<endl; //It works, because it takes from the _localPropRep, and it passes it as value!!! ps_h = graph_h->lookupLocalProp("name"); while(!ps_h.end()){ cout << "LocalProperties: "; p_h=ps_h.next(); cout << "Key: " << p_h.key() << " Value: " << p_h.value() <<endl; } // It does not work, because is accessing the propertystream_h from // the _globalPropRep (index of the tuple // {string globalkey, string value, propertystream_h props} // the propertystream_h it has as member a pair of iterators for another index. // -> after a lot of debugging (about 16h) OI found out that // it seems that during the creation of a graph, // when it passes the graph to graph_h, and goes out of scope, it keep the // iterator reference to the first element, but just that... the next // gives me segmentation fault. Anyone knows how to pass the graph and the its members // the indexes-repositories as value, so it would not depend on the pointing to // the graph that was freed from the memory? gpit = graph_h->properties("*"); if (!gpit) cout << "Not found any property in the globalProperties Repository."<<endl; else{ int i=0; while (!gpit.end()) { gp_h = gpit.next(); cout << "While_1::Iteration_" << ++i << endl; cout << "GlobalProperty key: " << gp_h.key() << endl; cout << "GlobalProperty value: " << gp_h.value() << endl; ps_h = gp_h.propertyStreamHandler(); int j = 0; while (!ps_h.end()){ p_h = ps_h.next(); cout << "While_2::Iteration" << ++j << endl; cout << "GlobalProperty::PropertyStream: key " << p_h.key() << endl; cout << "GlobalProperty::PropertyStream: value " << p_h.value() << endl; } } } } -- ************************************************* Rodrigo Dias Ferreira Master Student of Computational Engineering Technische Universität Dresden - Germany Mobile Phone:+49 171 3158797 E-mail: rodrigodias(a)gmx.de ************************************************* Jetzt 1 Monat kostenlos! GMX FreeDSL - Telefonanschluss + DSL für nur 17,95 Euro/mtl.!* http://dsl.gmx.de/?ac=OM.AD.PD003K11308T4569a

2 1

boost::interprocess::managed_mapped_file and cross arch?
by Ben Martin 06 Feb '09

06 Feb '09

Hi, Has anyone got any tips on using boost::interprocess::managed_mapped_file with the managed_mapped_file::segment_manager allocators and the boost/interprocess/containers in a memory mapped file which can be used across x64 and arm platforms? As everything should be using offset pointers, I get the feeling that there should be some way to make this cross platform utopia happen but thought I'd ask before serious tinkering attempts.

2 1

std::back_inserter() with move semantics?
by Robert Dailey 06 Feb '09

06 Feb '09

Hi, I'm currently using std::back_inserter on a ptr_vector, and the values being inserted are boost::unique_ptr's. back_inserter does simple assignment but I need it to call boost::move() on the thing being assigned (inserted). Does boost have an algorithm that can do this?

1 1

boost::bind
by Hansi 06 Feb '09

06 Feb '09

Hello, I have a problem using boost::bind (version 1.34.1). I don't know whot I make wrong but I think that I can use it in my case. Or I'm wrong? I use VS2005. in some external header file I have the declaration typedef void (* FUNCTION)(int ,void *); void SetCallback(FUNCTION cb); Now I want to call a function inside my class. Maybe with bind? I have tested the following: SetCallback(boost::bind<void>(boost::mem_fn(&Program::OnCallback),this,_1,_2)); but this does not work..have anyone an hint how I can do that? Regards Hansjörg

3 3

[ptr_container] ptr_map and cloning issues
by Robert Dailey 06 Feb '09

06 Feb '09

I have a ptr_map as follows: typedef boost::ptr_map<std::string, Texture> TextureContainer; I only use forward declarations of Texture where needed. When I'm iterating over an instance of TextureContainer, I expect to not have to do more than use the forward declaration since technically we're only iterating pointer values and the definition of Texture is not needed for this. So when I do this: TextureContainer myTextures; TextureContainer::const_iterator it = myTextures.find( "some key" ); The above (second line) results in an extremely complex and long compiler error, but the important part of the error says what I have pasted below. Why is this error happening? Is it trying to clone Texture objects? This shouldn't be happening. *boost/ptr_container/clone_allocator.hpp(34) : error C2514: 'rs::Texture' : class has no constructors C:\IT\work\planb\components\rs/renderer/TextureFwd.hpp(6) : see declaration of 'rs::Texture' C:\IT\work\planb\third_party\boost\1_37_0\boost/ptr_container/clone_allocator.hpp(55) : see reference to function template instantiation 'T *boost::new_clone<U>(const T &)' being compiled*

3 7

boost and std collisons in c++0x
by Ein Held 06 Feb '09

06 Feb '09

Hello I would like to know more about boost's general attitude towards c++0x and the collisions of boost with std. As of now, we move both, ::boost- and ::std-namesspace in the global namespace via using xxx. This is exactly what we want - boost and the stl are both such fundamental libraries that using an explicit namespace specifier everytime we want to use content of these namespaces is not accaptable. This would just blow the code and make it unreadable. Once we move up to c++0x, we will not be able to keep this way of coding up. ::std::tr1 is merged into ::std and so the former tr1 classes will collide with the boost ones if explicit namespace identifiers are missing. I would like to stress the fact that code, perfectly fine to the boost documentation, will fail to compiler most likely. #include <iostream> //This one might include <array> using namespace std; #include <boost/array.hpp> using namespace boost; array<int,1> blub; //fail Is there anything planned to prevent this happen? Thank you

6 8

[iterator] - does there exist an opposite of Function Output Iterator?
by Michael Fawcett 06 Feb '09

06 Feb '09

http://www.boost.org/doc/libs/1_37_0/libs/iterator/doc/function_output_iter… Shows a unary function being adapted as an OutputIterator. Does Boost have something that does the opposite, i.e. takes an OutputIterator and adapts it as a unary function object? In my own code I currently have: template <typename OutputIterator> struct output_iterator_function { explicit output_iterator_function(OutputIterator i) : iter(i) { } template <typename T> void operator()(const T &v) { *iter++ = v; } OutputIterator iter; }; template <typename OutputIterator> output_iterator_function<OutputIterator> make_output_iterator_function(OutputIterator i) { return output_iterator_function<OutputIterator>(i); } If this doesn't already exist in Boost.Iterator, it seems like it would nicely complement the already existing function_output_iterator. --Michael Fawcett

3 4

glibc detected corrupted doubly-linked list (unit test)
by Ross Boylan 05 Feb '09

05 Feb '09

I get error shown below when I try to test my program. It appears to be coming directly out of the unit test framework, though this is after a test, and so my code could have done something. Can anyone help me determine what is going on or how to fix it? Valgrind shows the error, but it's source is mysterious. This was generated on Debian GNU/Linux etch with 64 bit Xeon and gcc. The same tests run fine on Debian testing with 32 bit AMD and OS-X on 64 bit powerpc (although I think the older version of the OS on the machine is mostly 32 bit). *** glibc detected *** corrupted double-linked list: 0x00000000005fd2a0 *** Program received signal SIGABRT, Aborted. 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 Current language: auto; currently c (gdb) where #0 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 #1 0x00002affd559384e in *__GI_abort () from /usr/lib/debug/libc.so.6 #2 0x00002affd55c85f9 in __libc_message () from /usr/lib/debug/libc.so.6 #3 0x00002affd55cd9cc in malloc_consolidate () from /usr/lib/debug/libc.so.6 #4 0x00002affd55cf789 in _int_malloc () from /usr/lib/debug/libc.so.6 #5 0x00002affd55d116d in *__GI___libc_malloc () from /usr/lib/debug/libc.so.6 #6 0x00002affd518f93d in operator new () from /usr/lib/libstdc++.so.6 #7 0x00002affd516e5d1 in std::string::_Rep::_S_create () from /usr/lib/libstdc++.so.6 #8 0x00002affd516ef8b in std::string::_Rep::_M_clone () from /usr/lib/libstdc++.so.6 #9 0x00002affd516f895 in std::string::reserve () from /usr/lib/libstdc ++.so.6 #10 0x00002affd51690a5 in std::basic_stringbuf<char, std::char_traits<char>, std::allocator<char> >::overflow () from /usr/lib/libstdc++.so.6 #11 0x00002affd516da8d in std::basic_streambuf<char, std::char_traits<char> >::xsputn () from /usr/lib/libstdc++.so.6 #12 0x00002affd5163512 in std::operator<< <std::char_traits<char> > () from /usr/lib/libstdc++.so.6 #13 0x00002affd4fbb175 in boost::unit_test::results_collector_t::test_unit_finish () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #14 0x00002affd4fb8180 in boost::unit_test::framework_impl::visit () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #15 0x00002affd4fc9f1b in boost::unit_test::traverse_test_tree () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #16 0x00002affd4fb72d8 in boost::unit_test::framework::run () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #17 0x00002affd4fc2b35 in main () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #18 0x00002affd557f4ca in __libc_start_main () from /usr/lib/debug/libc.so.6 #19 0x000000000040420a in _start () at ../sysdeps/x86_64/elf/start.S:113 -- Ross Boylan wk: (415) 514-8146 185 Berry St #5700 ross(a)biostat.ucsf.edu Dept of Epidemiology and Biostatistics fax: (415) 514-8150 University of California, San Francisco San Francisco, CA 94107-1739 hm: (415) 550-1062

1 0

Citing Boost libraries
by Niko Vuokko 05 Feb '09

05 Feb '09

Hi, I remembered once seeing an entry on the website saying how one should cite the Boost project. Now however I can't find it when I'd need it. Thus, is 'Boost Project, http://www.boost.org' enough or is there some policy on citing? Niko Vuokko

2 1

Any restriction on adding a boost/sandbox library to dmoz (open directory)?
by er 05 Feb '09

05 Feb '09

Hello, Are there any restrictions on adding a boost/sandbox library that I wrote under the boost license to dmoz (open directory project) to facilitate online searches?

1 0

Re: [Boost-users] proto: analytical-only math functions
by Hicham Mouline 05 Feb '09

05 Feb '09

> ----- Original Message ----- > From: "Eric Niebler" <eric(a)boost-consulting.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] proto: analytical-only math functions > Date: Thu, 05 Feb 2009 08:40:05 -0800 > > > Hicham Mouline wrote: > > Hi Eric, > > > > Thank you for the LHS grammar. I have made the changes you suggested in the > > attached files. > > > > The main header <math.h> (I'll change this name later) includes constants > > (c0 ... c100), variables(x0... x100 and x y z S r q v t), basic functions > > from <cmath> and general functions defined by the user, with dimensions 0 to > > 100. > > > > Question1: With PP, I define constants c0 to c100, as non-const because I > > let the user initialize them to a integer variables or literals or floating > > point variables or literals. > > I don't understand, but it probably doesn't matter. PP is boost.preprocessor. I forgot attached files don't appear in the mailing list. template <unsigned int subscript> struct constant_tag {}; proto::terminal< constant_tag<0> >::type c0 = {{}}; // with preprocessor, i define c0 ... c100 I don't want lib users, in a first use, to have to define constant names nor variable names themselves. > > Does the non-constness matter? They are defined in a header file included by > > users of the library. > > You'll have linker trouble if two translation units include that header. You > should define them in a .cpp file and mark them as extern in the header. Right. Could i define them const and still assign values (like arithmetic literals) to them later on? > > > Queestion3: I made dimension_of a numerical metafunction with an embedded > > value member. > > OK, that's reasonable. > > > What is the convenience > > of making metafunctions numerical? > > I don't know what you're asking. I'm just asking about a general advice re whether to make metafunctions numerical whenever possible. > > Question4: What is a quick way to test fundef_lhs_grammar does what I > > intend? > > When I want to test a grammar, I define two functions like this: > > template<typename E> > void assert_matches( E const & ) > { > BOOST_MPL_ASSERT((proto::matches<E, fundef_lhs_grammar>)); > } > > template<typename E> > void assert_not_matches( E const & ) > { > BOOST_MPL_ASSERT_NOT((proto::matches<E, fundef_lhs_grammar>)); > } > > Then in main(), I can create expressions and pass them to one of these > functions. Either it matches or it doesn't, and I can find out at compile time. > Great, will do. I'll leave the grammar of the RHS of = operator till later. My next question is about my constants. I want to allow this example of syntax: c35 = any expression of integral or floating point literals, of c++ runtime variables of integral or fp type (no bool no enums) of _other_ constants Later, a constant will be either undefined, or defined. if undefined, evaluations of expressions with that constant will keep that constant in, otherwise, the constant will be replaced by its value How do I write the grammar that allows any expression, but just with those 4 possibilies (c35)? regards,

2 1

boost::lambda: how to create indirect functor
by ＠ 05 Feb '09

05 Feb '09

prerequisites: struct C { void func(int i) {} }; void indirect(boost::function<void(C*)> f) { static C c; f(&c); } I need a functor that takes int and calls "indirect" passing there &C::func bound with that int. I imagine a solution like: boost::function<void(int)> result_functor = bind(indirect, bind(&C::func, protect(_1), _1)); receiving compilation error: "could not deduce argument" deep inside lambda library thanks -- View this message in context: http://www.nabble.com/boost%3A%3Alambda%3A-how-to-create-indirect-functor-t… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

Re: [Boost-users] [boost] [SVG Plot] What happened to this library?
by Marc Viala 05 Feb '09

05 Feb '09

Hello, I have just checked out the latest release of SVG Plot library from https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ and tried to compile one source example w/ VC++ 7.1 against Boost 1.37.0 but the compilation failed. The file source is "1d_simple.cpp" from the of SVG Plot example directory. The compilation of the source file fails with the following error: 'svg_color_constant' unknown identifier in file svg_color.hpp @ line37 Did I miss something? Best regards, Marc Viala > -----Message d'origine----- > De : boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] > De la part de Paul A. Bristow > Envoyé : jeudi 5 février 2009 10:35 > À : boost(a)lists.boost.org > Objet : Re: [boost] [SVG Plot] What happened to this library? > > > -----Original Message----- > > From: boost-bounces(a)lists.boost.org [mailto:boost- > bounces(a)lists.boost.org] > On > > Behalf Of Joel > > Sent: 04 February 2009 23:45 > > To: boost(a)lists.boost.org > > Subject: [boost] [SVG Plot] What happened to this library? > > > > Paul A. Bristow <pbristow <at> hetp.u-net.com> writes: > > > 3 I am close to updating the documentation (and enhanced code) > > > for the > GSoC > > > 2007 SVG plot project by Jake Voytko - including Doxygenation and > > > John Maddock's auto indexing. The code is in a useful (but > > > unpolished) state > and > > > I am confident it will allow neat graphs to display data like > time_series > > > with minimal programming effort. The SVG files produced are tiny, but > high > > > quality, and can be viewed with quality browsers. > > > Is there a URL for this current version of the code? A quick look > > on > google > > only found me Jake's site which is from August 2007: > > > > http://www.jakevoytko.com/code.php > > That is way out of date. > > There is the latest version on SVN > > https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ > > but I am still actively working on it (especially the docs) so use at > your own risk (peril even!). > > Feedback welcome of course. > > > Also, will there be boost graph support? > > Not unless you provide it ;-) > > Paul > > --- > Paul A. Bristow > Prizet Farmhouse > Kendal, UK LA8 8AB > +44 1539 561830, mobile +44 7714330204 > pbristow(a)hetp.u-net.com > > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

1 0

ASIO sockets and stream buffers
by Jeff Diewald 05 Feb '09

05 Feb '09

I'm having trouble with trying to connect my TCP sockets up to a stream buffer, and need some help. I've already opened my sending socket, or accepted a connection to get a new receiving socket, and I want to send messages back and forth. What I'd like to write is something like: void sendMessage(boost::asio::ip::tcp::socket* s) { ?? some stream type ?? str(s); str << ... write stuff ... << flush(); str >> ... read stuff ...; } I can't seem to find the right stream type that takes my existing socket. Does such a creature exist in the ASIO library? Help! Thanks in advance, Jeff Diewald JEOL USA

2 1

Re: [Boost-users] boost and std collisons in c++0x
by Daniel Lidström 05 Feb '09

05 Feb '09

Hello, here is how I have solved this problem where I work: Create a header for each class that you want to use, that exists in both boost and std::tr1. For example, here's our local shared_ptr.h: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils = std::tr1; #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils = boost; #endif #endif If you also have to rely on VC6 (as we do) then you can't selectively import parts from a namespace (using boost::shared_ptr doesn't work). But if you only use more modern compiler, you can do this: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils { using std::tr1::shared_ptr; using std::tr1::enable_shared_from_this; } #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils { using boost::shared_ptr; using boost::enable_shared_from_this; } #endif #endif Hope this helps! Regards, Daniel Lidström Stockholm, Sweden _____ From: Ein Held [mailto:held_ein@yahoo.de] Sent: Wednesday, February 04, 2009 1:23 PM To: boost-users(a)lists.boost.org Subject: [Boost-users] boost and std collisons in c++0x Hello I would like to know more about boost's general attitude towards c++0x and the collisions of boost with std. As of now, we move both, ::boost- and ::std-namesspace in the global namespace via using xxx. This is exactly what we want - boost and the stl are both such fundamental libraries that using an explicit namespace specifier everytime we want to use content of these namespaces is not accaptable. This would just blow the code and make it unreadable. Once we move up to c++0x, we will not be able to keep this way of coding up. ::std::tr1 is merged into ::std and so the former tr1 classes will collide with the boost ones if explicit namespace identifiers are missing. I would like to stress the fact that code, perfectly fine to the boost documentation, will fail to compiler most likely. #include <iostream> //This one might include <array> using namespace std; #include <boost/array.hpp> using namespace boost; array<int,1> blub; //fail Is there anything planned to prevent this happen? Thank you

1 0

[Accumulator] Build error in using BOOST::accumulator on WXP VC8
by dhruva 05 Feb '09

05 Feb '09

Hello, I am using BOOST::accumulator from 1.37. I get the following warning in the build on WXP using VC8 (MSVC 2005). I am exploring to find out where the problem could be, posting to find is someone has experienced this problem. Since our build treats warnings as errors, I am stuck. ...include\boost/fusion/container/vector/detail/deref_impl.hpp(46) : warning C4003: not enough actual parameters for macro 'index' -dhruva -- Contents reflect my personal views only! Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/

3 3

[Python] Expose c++ instances to python
by Germán Diago 05 Feb '09

05 Feb '09

Hello. I'm trying to embed python to an application. I did that with success and I'm using boost.python to make some bindings to my API. What I would like, is that the interpreter has access to my objects at runtime, namely, I don't want to create objects from python code but to use the c++ objects, created in my c++ application, from python (and I have wrappers for those in boost.python). I don't know how to achieve this. I just know how to wrap classes, but I have no idea how to expose instances. Any idea how to achieve this? I googled and found nothing clear. Thanks in advance.

2 2

[serialization] Sending user data to serialize()?
by Robert Dailey 04 Feb '09

04 Feb '09

Hi, I have a complex case I'm trying to work with. I may be doing this completely wrong so if there is a better design for this I'm always open for that. However for now I'm going to assume my particular problem can be solved. There exists two classes: A and B. Class A is defined as such: class A { public: template< typename Archive > void load( Archive& archive, unsigned int ) { archive & m_listOfB; } private: std::vector<int> m_listOfInt; boost::ptr_vector<B> m_listOfB; }; And class B is defined roughly as: class B { public: template< typename Archive > void load( Archive& archive, unsigned int ) { // Code isn't important here } }; Here's the problem: For each B that is deserialized by A::load(), I need to pass in a reference to m_listOfInt. So, essentially the load() function in B would look something like this: void load( Archive& archive, unsigned int, std::vector<int>& listOfInt ) { } I was hoping boost.bind could be used somewhere, but I just don't see how. One way to solve the problem is to call B::load() explicitly with the extra parameter, but I don't think that's an appropriate solution. Any ideas on how to solve this? Or perhaps I'm trying to solve the wrong problem.

3 3

[boost.asio] repeating a timer
by Sean Farrow 04 Feb '09

04 Feb '09

Hi: I've just been looking at the boost asio timers, I was wondering whetherthere is a repeat timer, so that my call back will be executed everytime the timer completes. This needs to execute more than once. Any help apreciated. Sean.

2 1

Finding the n smallest items in a list
by Ruediger Berlich 04 Feb '09

04 Feb '09

Hi there, I'm searching for a method to find the n smallest numbers in a list of m >> n numbers. The n numbers need to be sorted. m will usually be in the range of 100-1000, n will be 5 or less. So far I'm simply sorting the entire vector, which I assume is not very efficient, as the other m-n items in the container can remain unsorted. Is there a function in Boost that can help me in this situation ? Best Regards, Ruediger

4 4

[date_time] posix_time::time_duration::operator<< fails for hours>23
by Soren Dreijer 04 Feb '09

04 Feb '09

I'm creating a posix_time::time_duration object based on the minutes() helper function. If I specify a large value, such as 2000, I get a time_duration of 33:20:00. Take a look at the following piece of code, though: time_duration td = minutes(2000); cout << to_simple_string(td); // OK cout << td; // Fails with an assertion in VS2008 The latter call fails with the following assertion in strftime.c on line 658: _VALIDATE_RETURN( ( ( timeptr->tm_hour >=0 ) && ( timeptr->tm_hour <= 23 ) ), EINVAL, FALSE) Apparently, operator<< expands to _expandtime(), which doesn't allow values for the hour to be greater than 23. Is this intended behavior, or should I just always use to_simple_string() rather than the convenient operator<< ?

2 1

[asio] how to handle sync_accept error to avoid server hang on?
by tomasz jankowski 04 Feb '09

04 Feb '09

hello, actualy I'm testing my server. I'm making new connections faster than server is able to handle it. because of it server quickly is getting from system errno 24 (Too many open files). because of chaining async operation in asio design async_accept handler like below lead to server hang on. void AnldServer::handle_accept(const boost::system::error_code& e) { if (!e) { new_connection_->start(); new_connection_.reset(new AnldConnection(io_service_, request_handler_)); acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); }else{ NDSLOG_NOTICE_S() << "Accept error: " << e << "\n"; } } Since we are not starting a new accept operation the io_service will run out of work to do and the server will hang on (if it was daemonised) or exit(if not). ofcourse server in production environment couldn't behaves like this. server must can handle such situation. my question is: how to fix it? just start async_accept without creating new_connection in case of error? like this for example? void AnldServer::handle_accept(const boost::system::error_code& e) { if (!e) { new_connection_->start(); new_connection_.reset(new AnldConnection(io_service_, request_handler_)); acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); }else{ NDSLOG_NOTICE_S() << "Accept error: " << e << "\n"; acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); } } I have just tested above code - it seems to work fine. but maybe someone have beter solution> or maybe it is good idea to add sleep(5) before async_accept in case of error? thanks, tom ---------------------------------------------------- Twoja rodzina na bliscy.pl Zobacz: http://klik.wp.pl/?adr=http%3A%2F%2Fcorto.www.wp.pl%2Fas%2Fbliscy.html&sid=…

1 0

What does sys_err = 3 mean? or where can I find out?
by Andrew Bond 04 Feb '09

04 Feb '09

I am using Boost filesystem and I am getting an error (sys_err = 3). Where can I find a human-readable explanation of this error? Are there text explanations that can be included in my app to better inform the end user what the erro means? Any help will be much appreciated. Andrew Bond

2 2

Boost compatibility with Green Hills Integrity RTOS and Windows CE
by Vikas Goel 04 Feb '09

04 Feb '09

Hi, I am planning to use Boost libraries with Green Hills Integrity RTOS and Windows CE. Please let me know if there are any known issues (like build, compilation, etc) in running Boost on Green Hills Integrity RTOS and Win CE. Any comment regarding usage of Boost with any other RTOS is also welcome. Thanks & Regards, Vikas **************** CAUTION - Disclaimer ***************** This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended solely for the use of the addressee(s). If you are not the intended recipient, please notify the sender by e-mail and delete the original message. Further, you are not to copy, disclose, or distribute this e-mail or its contents to any other person and any such actions are unlawful. This e-mail may contain viruses. Infosys has taken every reasonable precaution to minimize this risk, but is not liable for any damage you may sustain as a result of any virus in this e-mail. You should carry out your own virus checks before opening the e-mail or attachment. Infosys reserves the right to monitor and review the content of all messages sent to or from this e-mail address. Messages sent to or from this e-mail address may be stored on the Infosys e-mail system. ***INFOSYS******** End of Disclaimer ********INFOSYS***

1 0

[signals (thread safe)] Scope of slot_call_iterator (or how to implement deferred signals)
by Fabio Fracassi 04 Feb '09

04 Feb '09

Hi, I am currently trying to implement deferred signals using boost signals (well thread safe signals). I had the (crazy?) idea that it might be possible to hijack the combiner interface to do this. The design rational said that during the signal call the state (including the arguments that were passed) are cached for the combiner. So, what I tried to do was to copy and store the first and last iterater out of the combiner, to iterate over them at a later time, to call the slots. What I don't know is whether the slot_call_iterator (and the data it uses ) stays in scope after the signal call (i.e. signal...::operator() ) returns. Here is what I tried: #include <boost/signal.hpp> #include <boost/tr1/memory.hpp> #include <queue> struct signal_queue { signal_queue() : m_signals() {} template <typename InputIterator> void add_signal(InputIterator first, InputIterator last) { m_signals.push( std::tr1::shared_ptr<sig_iterator_range_placeholder>( new sig_iterator_range_holder<InputIterator>(first, last))); } bool process_one_signal() { if (!m_signals.empty()) { std::tr1::shared_ptr<sig_iterator_range_placeholder> sig = m_signals.front(); m_signals.pop(); sig->send(); return true; } return false; } private: struct sig_iterator_range_placeholder { virtual void send() = 0; }; template <typename InputIterator> struct sig_iterator_range_holder : sig_iterator_range_placeholder { sig_iterator_range_holder( InputIterator first, InputIterator last) : m_first( first ), m_last( last ) {} virtual void send () { while (m_first != m_last) { *m_first++; } return; } private: InputIterator m_first; InputIterator m_last; }; std::queue< std::tr1::shared_ptr<sig_iterator_range_placeholder> > m_signals; }; struct defered_send { typedef void result_type; template<typename InputIterator> void operator()(InputIterator first, InputIterator last) const { s_signalQueue.add_signal( first, last ); } static signal_queue s_signalQueue; }; signal_queue defered_send::s_signalQueue = signal_queue(); // Tests struct test_slots { void operator()() const { std::cout << "exec Slot()" << std::endl; } void operator()(int t1, int t2) const { std::cout << "exec Slot(" << t1 << ", " << t2 << ")" << std::endl; } }; int main () { boost::signal<void ( int, int ), defered_send> def_ii; test_slots test; def_ii.connect(test); std::cout << "Send Defered Signals ... " << std::endl; def_ii(42, 24); // <- Point 1 std::cout << "Entering 'event loop' ... " << std::endl; while ( defered_send::s_signalQueue.process_one_signal() ) {} std::cout << "Done." << std::endl << std::flush; return EXIT_SUCCESS; } The good news is that it doesn't crash, though I suspect that this is pure luck. After the slot call (Point 1) some things go out of scope (most notably the cache variable in slot_call_iterator). Now to make a long story short. Is what I am trying to do possible? If not should it? Or do I have to find another way to achive this? If so does someone have a hint? Regards Fabio

2 2

Re: [Boost-users] Transferring files across a network.
by Andrew Maclean 04 Feb '09

04 Feb '09

To all those who helped, especially Rahul who very kindly made some sample code available and put me on the right track. I now have a client and a server that can handle multiple files being sent over the network. The files are attached for your interest. If anyone can improve them I really will welcome their comments. If there is a need, it is Ok to include them as examples in the ASIO documentation. I have no issues with this. Thanks once again to everyone who helped. Regards Andrew

3 7

Problem transforming a vector<bool> to a vector<any>
by Fabrice_CBA 04 Feb '09

04 Feb '09

Hi everyone, I am working on a project in which I'm using a "simplified" version of the boost::any library. By simplified, I mean that I got rid of the #defines and made it independent from the rest of boost. The changes are very small, and in my opinion shouldn't impact much the class, since the general structure is still there. My implementation is attached to this message. http://www.nabble.com/file/p21822878/Any.h Any.h However I am having a problem transferring a vector<bool> into a vector<any>. It works for any other types I've tested, only booleans fail. Here is an example: std::vector<std::string> source0(1, "SomeString"); std::vector<long> source1(1, 666); std::vector<bool> source2(1, true); std::vector<double> source3(1, 6.66); std::vector<any> destination; destination.push_back(source0[0]); destination.push_back(source1[0]); destination.push_back(source2[0]); destination.push_back(source3[0]); When checking what is in destination[2], it seems it only holds {...}, and not the original {true}. Whereas it works perfectly for the other values. Any idea on what I'm doing wrong? Any help appreciated. Thanks, Fabrice -- View this message in context: http://www.nabble.com/Problem-transforming-a-vector%3Cbool%3E-to-a-vector%3… Sent from the Boost - Users mailing list archive at Nabble.com.

2 2

How to convert boost::posix_time::ptime to FILETIME structure?
by Archie14 03 Feb '09

03 Feb '09

Is there any helper function to convert boost::posix_time::ptime to FILETIME? I am trying to pass datetime value from boost-based app to another (C#). Looks like that FILETIME (that can be represented as long) is a good option, besides string. May be there is better alternative?

1 1

Nullary metafunction
by er 03 Feb '09

03 Feb '09

Hi All, I'm looking for template<typename> class F such that F<T>::type is T::type if it exists, T itself otherwise. I was hoping apply<T>::type would work, by analogy with the well known example apply<std::vector<_>,X>::type, but apparently not.

3 3

Thread locks
by Larry E. Ramey 03 Feb '09

03 Feb '09

Under 1.33.1 we used to do this: boost::try_mutex::scoped_try_lock lock(m_mutex); if (lock.locked() && m_threadState == UploadMap) { I'm not sure, but I think under 1.37 I should do: boost::try_mutex::scoped_try_lock lock(m_mutex); if (lock.owns_lock() && m_threadState == UploadMap) { When I do that, I get a crash when I exit that I never used to have. Any ideas? Larry

2 2

[boost-users][lambda] crash in std::for_each
by Igor R 03 Feb '09

03 Feb '09

The following code crashes in for_each when trying to output the 1st pair. What's wrong with it? Thanks! namespace bl = boost::lambda; std::map<std::string, std::string> temp; temp["a"] = "1"; temp["b"] = "2"; const std::map<std::string, std::string> attrs(temp); typedef std::pair<std::string, std::string> string_pair; std::stringstream stream; std::for_each(attrs.begin(), attrs.end(), stream << bl::bind(&string_pair::first, bl::_1) << bl::bind(&string_pair::second, bl::_1));

4 7

[asio] Cloning a WSA socket (windows)
by Tore Halvorsen 03 Feb '09

03 Feb '09

Hi, I am trying to clone a socket from process to another, mostly for having one process per client in a network server. Some legacy stuff makes this the only design possible, so the threaded approach is simply not feasible... Anyway, when I'm trying to create a boost socket from a cloned WSA socket I get an exception. class boost::exception_detail::clone_impl< struct boost::exception_detail::error_info_injector< class boost::system::system_error > > : The parameter is incorrect This same happens for this example program, using boost 1.37 Does anyone have an idea why this does not work? #ifndef _WIN32_WINNT #define _WIN32_WINNT 0x0501 #endif #define WIN32_LEAN_AND_MEAN #define NOMINMAX #include <windows.h> #include <winsock2.h> #pragma comment(lib, "ws2_32") #include <boost/asio.hpp> namespace ip = boost::asio::ip; int main_impl(int argc, char* argv[]) { boost::asio::io_service ios; ip::tcp::socket s(ios); ip::tcp::acceptor a(ios, ip::tcp::endpoint(ip::tcp::v4(), 1777)); a.accept(s); WSAPROTOCOL_INFO info; if (WSADuplicateSocket(s.native(), GetCurrentProcessId(), &info)) { std::cerr << "WSAError: " << WSAGetLastError() << std::endl; return EXIT_FAILURE; } // pass info over a pipe to the client... SOCKET copy(WSASocket(FROM_PROTOCOL_INFO, FROM_PROTOCOL_INFO , FROM_PROTOCOL_INFO, &info, NULL, NULL)); ip::tcp::socket scopy(ios, ip::tcp::v4(), copy); return EXIT_SUCCESS; } int main(int argc, char* argv[]) { try { return main_impl(argc, argv); } catch(std::exception const& ex) { std::cerr << typeid(ex).name() << ":" << ex.what() << std::endl; return EXIT_FAILURE; } } -- Eld på åren og sol på eng gjer mannen fegen og fjåg. [Jøtul] <demo> 2009 Tore Halvorsen || +052 0553034554

2 4

[mpi] Non-default arguments for running regression tests through bjam
by Pete Bartlett 03 Feb '09

03 Feb '09

Dear Boosters, I am just going through the learning curve for Boost.MPI. My underlying target platform is MPICH2 on Windows XP/Vista. Given I am taking baby-steps I would like run the regression tests to check my install. Mpirun doesn't exist in my install - mpiexec is required instead. The docs and mpi.jam comments say "The (optional) fourth argument configures Boost.MPI for running regression tests. These parameters specify the executable used to launch jobs (default: "mpirun") followed by any necessary arguments to this to run tests and tell the program to expect the number of processors to follow (default: "-np")." I'm no jam expert, but that suggests that my user-config.jam should change to using mpi : : <find-shared-library>cxx <find-shared-library>mpi <library-path>C:/MPICH2/lib <include>C:/MPICH2/include : : mpiexec -n ; where the " : : mpiexec -n " is the new part. However this results in a slew of jam errors. I am able to run the regression tests by hacking mpi.jam to change the defaults, however I'd prefer to know the correct syntax in user-config.jam please. Thanks in advance for any help, Pete Bartlett

2 2

Boost.lambda: can I do this with a lambda function (multiplestatements?
by Joost Kraaijeveld 03 Feb '09

03 Feb '09

Hi, I want to embed some debug printing in a lambda function which is a predicate used to remove elements from a vector like this: collection.erase( std::remove_if( collection.begin(), collection.end(), boost::lambda::if_then_else_return( boost::lambda::_1 <= "s5", // if (std::cout << "deleted: " << boost::lambda::_1, true), // then (std::cout << "not deleted: " << boost::lambda::_1, false ))), // else collection.end()); This actually compiles, runs and removes all the right elements but it does not print for every element it is checking. It just prints "not deleted: deleted: s4s5s6s8" , the last string being all the elements of the collection. Is what I want possible and if so how? TIA, -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 web: www.askesis.nl

2 1

Boost:interprocess 1.36.0 - Minimum size for a shared memory segment
by Federico Golfrè Andreasi 03 Feb '09

03 Feb '09

Hi ! which is the minimum number of bytes I have to allocate to construct a managed shared memory? Or how can I calculate it? I did some tests and I believe is 112 bytes for 32 bit machines and 224 bytes for 64 bit, am I right ? And for the allocators? What I want to do is set the size of the shared memory smaller than I can, knowing the dimension of the variables I want to put in; even if the code is compiled in 64 bit or 32 bit machines. Thank you, Federico

2 1

boost::tokenizer with char*
by Archie14 03 Feb '09

03 Feb '09

I was wandering if anyone can help me to understand how to use boost::tokenizer with char* buffer. tokenizer template parameters include string as default Type. I don't want to copy char* into string.

1 1

Using SFINAE to detect presence of member function - Unreliable
by Naik, Roshan 03 Feb '09

03 Feb '09

I have taken a look at anything I could find through Boost lists and Google that came up as a solution to the problem of detecting the existence of a member function in a type... using SFINAE. All of them have one problem.. they are unable to detect the existence of the member function if it was defined in a base class. They can only detect if the member function was directly defined in the class being tested. At their heart, all solutions boil down to some variation of the following template class with a template parameter that is a (non-type) pointer to member function: template<class T, void (T::*)(void) > struct Tester; Then we try to SFINAE on it by the usual sizeof trick. However the problem is that if method 'void foo(int)' is defined in a Base class. Then the type of &Derived::foo is actually void (Base::*)(int) ... and not void (Derived::*)(int) Although during argument passing the conversion of the Base member function pointer to Derived member function pointer is acceptable to C++, it will NOT do such conversion when instantiating templates. So trying to use Tester<Derived, &Derived::foo> will always fail us if 'foo' is defined in Base. So .. my question is ....does anyone have solution that works for the case when the method is defined in the base class too ? I am thinking ... if it is possible to extract the class name from the actual type of &Derived::foo, then the problem can be solved... but the type extraction mechanism must not error out on types that have absolutley no member function called foo. I know type erasure (which i prefer to call External polymorhism) can solve this issue but SFINAE is more efficient at runtime. -Roshan

3 7

[asio] How to get the name of the endpoint from the ip address of the endpoint.
by Andrew Maclean 03 Feb '09

03 Feb '09

If I have an endpoint as an ip address (IP V4 or IPv6), how can I do a DNS lookup to get the name of the endpoint? In the example below, I understand that the host_name is coming from the query. But how do I do a lookup to get the host name from the IP? This may help. If I do something like this: ip::tcp::resolver_iterator res = ip::tcp::resolver(ios).resolve(ip::tcp::resolver_query("google.com", "80")); for(;res != ip::tcp::resolver_iterator(); ++res) { std::cout << res->host_name() << ":" << res->service_name() << " "; std::cout << res->endpoint().address().to_string() << std::endl; } The the output is: google.com:80 209.85.171.100 google.com:80 74.125.67.100 google.com:80 74.125.45.100 However if I do: ip::tcp::resolver_iterator res = ip::tcp::resolver(ios).resolve(ip::tcp::resolver_query("209.85.171.100", "80")); I get: 209.85.171.100:80 209.85.171.100 so th ehosr name comes from the query. I really want: google.com:80 209.85.171.100 Thanks in advance for any help. Andrew -- ___________________________________________ Andrew J. P. Maclean Centre for Autonomous Systems The Rose Street Building J04 The University of Sydney 2006 NSW AUSTRALIA Ph: +61 2 9351 3283 Fax: +61 2 9351 7474 URL: http://www.acfr.usyd.edu.au/ ___________________________________________

2 1

Question in usage of boost::bind
by Archie14 03 Feb '09

03 Feb '09

Below is an example that fails to compile. I have a vector of pointers to a templated class and I need to use find_if. My understanding of boost::bind. is that the first argument, when binding member function, is an explicit "this" pointer, that should be A* in my case. Any help in explaining what I am doing wrong will be greatly appreciated. #include <algorithm> #include <string> #include <vector> #include <boost/bind.hpp> #include <algorithm> #include <string> #include <vector> #include <boost/bind.hpp> template<typename T> class A { T _val; public: A(T val) : _val(val){}; T Val() {return _val;} bool CompareByVal(A<T>* a, int iType, T ofval) { return ( (a != NULL) && (iType == 1) && (a->Val() == ofval) ); } }; int _tmain(int argc, _TCHAR* argv[]) { std::vector<A<int>*> a; std::find_if (a.begin(), a.end(), boost::bind(&A<int>::CompareByVal, _1, _2, 1,1)); }

3 2

[Proto] proto::reverse_fold_tree
by Kim Kuen Tang 02 Feb '09

02 Feb '09

Hi all, i want to use the function proto::reverse_fold_tree to build a heterogeneous list from the expression "((a*b+c)*d+e)*f". The resulting sequence only contains the two terminals 'a' and b'. So i am a little bit confused. But using the function proto::fold_tree it produces correctly the sequence [f,e,d,c,b,a]. (Btw the two functions proto::fold_tree and proto::fold produce the same sequence [f,e,d,c,b,a], what is their difference? ) Here is the code: #include <iostream> #include <boost/proto/proto.hpp> #include <boost/proto/proto_typeof.hpp> #include <boost/fusion/container.hpp> #include <boost/fusion/algorithm/iteration.hpp> #include <boost/fusion/include/iteration.hpp> #include <boost/typeof/typeof.hpp> namespace mpl = boost::mpl; namespace proto = boost::proto; namespace fusion = boost::fusion; using proto::_; proto::terminal<char>::type const a = {'a'}; proto::terminal<char>::type const b = {'b'}; proto::terminal<char>::type const c = {'c'}; proto::terminal<char>::type const d = {'d'}; proto::terminal<char>::type const e = {'e'}; proto::terminal<char>::type const f = {'f'}; struct FoldToList : proto::or_< proto::when<proto::terminal<_>,fusion::cons<proto::_value, proto::_state>(proto::_value, proto::_state) > ,proto::when<proto::nary_expr<_,proto::vararg<_> >, proto::fold_tree<proto::_,fusion::nil(),FoldToList > > > {}; struct FoldToListReverse : proto::or_< proto::when<proto::terminal<_>,fusion::cons<proto::_value, proto::_state>(proto::_value, proto::_state) > ,proto::when<proto::nary_expr<_,proto::vararg<_> >, proto::reverse_fold_tree<proto::_,fusion::nil(),FoldToListReverse > > > {}; struct print { typedef void result_type; template<class T> result_type operator()(T const& t) const { std::cout<<t<<"\t"; } }; int main() { BOOST_PROTO_AUTO(expr, ((a*b+c)*d+e)*f ); proto::display_expr(expr); BOOST_MPL_ASSERT(( proto::matches<BOOST_TYPEOF(expr), FoldToList>)); BOOST_MPL_ASSERT(( proto::matches<BOOST_TYPEOF(expr), FoldToListReverse>)); BOOST_AUTO(sequence1,FoldToList()(expr)); fusion::for_each(sequence1,print()); std::cout << "\n--------------------\n"; BOOST_AUTO(sequence2,FoldToListReverse()(expr)); fusion::for_each(sequence2,print()); std::cout << "\n--------------------\n"; } Cheers Kim Tang

4 8

[boost.filesystem] query
by Sean Farrow 02 Feb '09

02 Feb '09

Hi: I am using boost.filesystem to hold a path including filename. would the function stem() of the path object give me the path excluding the filename? If i have: c:\program files\boost\welcome.txt The output wanted is: c:\program files\ Any help apreciated. Sean.

4 8

using boost.foreach with boost.array
by Sean Farrow 02 Feb '09

02 Feb '09

Hi: is it possible to use boost.foreach with boost.array? Cheers Sean.

2 1

Generate automatically an enum inside a template regarding to parameter
by Hansi 02 Feb '09

02 Feb '09

Hi, Is there a way to generate automatically an enum inside an template. I have e.g. the following template: template<int nr> class Test { enum { R1, ... Rx // where x is equal to nr }; } Thanks for any hint! Regards Hansjörg

1 0

Preprocessor to generate enum
by Hansi 02 Feb '09

02 Feb '09

Hi, what is the best way to generate the following enum with the preprocessor library (boost 1.34.1)? enum { R1=0, R2=1, ... }; Best regards Hansjörg

2 3

Re: [Boost-users] Compiler Error With boost::bind and boost::signals
by KERSAM 02 Feb '09

02 Feb '09

I forgot: I am using the Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 14.00.50727.762 for 80x86 and Boost Version 1.35. KERSAM wrote: > > Hello. > > I have a compiler error when I try to use boost::bind and boost::signals. > Here is the code: > > -------------------- > #include<boost/bind.hpp> > #include<boost/signals.hpp> > > class MyBoostTest { > public: > void testFunction(int x, int y) {} > }; > > > void doConnect() { > boost::signal2<void, int, int> signal; > signal.connect(boost::bind<void>(&MyBoostTest::testFunction, new > MyBoostTest, _1)); > } > ----------------------------------- > > The compiler gives me the following error: > c:\3rdparty\boost\boost\bind.hpp(289) : error C2064: term does not > evaluate to a function taking 2 arguments > class does not define an 'operator()' or a user defined conversion > operator to a pointer-to-function or reference-to-function that takes > appropriate number of arguments > > What am I doing wrong? > > Regards > -- View this message in context: http://www.nabble.com/Compiler-Error-With-boost%3A%3Abind-and-boost%3A%3Asi… Sent from the Boost - Users mailing list archive at Nabble.com.

3 3

std::wstring issue with Boost::FileSystem
by Sean Farrow 02 Feb '09

02 Feb '09

Hi: Whilst using boost::filesystem I'm getting the following issue: I've defines: std::wstring Process =ProcessToFind; //ProcessToFind is an input to the function I'm writing. std::wstring test =boost::filesystem::wpath(szModName).filename(); //szModName is obtained from a win32 api function. Process.Compare(test); //This line gives the following Error: 1>c:\work\access for everyone\dragonspeak\dragonspeak.cpp(45) : error C2039: 'Compare' : is not a member of 'std::basic_string<_Elem,_Traits,_Ax>' 1> with 1> [ 1> _Elem=wchar_t, 1> _Traits=std::char_traits<wchar_t>, 1> _Ax=std::allocator<wchar_t> 1> ] I'm using the trunk as of yesterday (feb 1) and visual studio 2005. Anyone any ideas what's going wrong, or what I've forgotten? Cheers Sean.

2 1

[Bind] Representing a member function as C function pointer?
by Roland Bock 02 Feb '09

02 Feb '09

Hi, maybe this is stupid, but I wonder if my code could become more elegant. I am using expat for XML parsing, which is working fine, but could be nicer: I have a class (XmlParser) which provides all the handlers for SAX parsing required by expat, but I can't figure out how to use them directly? When initializing expat, I give it a pointer to an XmlParser object and then register handlers: -------------------------- static void expatStartElementHandler (void* pUserData, const char* element, const char** attr) { XmlParser* xmlParser = reinterpret_cast<XmlParser*>(pUserData); xmlParser->startElement (element, attr); } static void expatEndElementHandler (void* pUserData, const char* element) { XmlParser* xmlParser = reinterpret_cast<XmlParser*>(pUserData); xmlParser->endElement (element); } void XmlParser::init() { parser_ = XML_ParserCreate ("UTF-8"); XML_SetUserData (parser_, this); XML_SetElementHandler (parser_, expatStartElementHandler, expatEndElementHandler); //... } ------------------------- I would prefer to get rid of those static non-member functions and their reinterpret_cast and do something like // does not work XML_SetElementHandler (parser_, boost::bind(&XmlParser::startElement, this, _2, _3), boost::bind(&XmlParser::endElement, this, _2)); Is there a nice way to do this with bind? Regards, Roland

2 2

passing a boost.array to a c function, and boost.System
by Sean Farrow 02 Feb '09

02 Feb '09

Hi list: I have a c function EnumProcesses in windows, and waswondering: 1. How can I pass a boost.array to this function, I need to pass the undedrlying array, not the boost.array class. 2. Does boost.system suppor the retrieval of operating system process in an stl-complient way, i.e using stl containers and allowing boost.Foreach to iterate over them. Cheers Sean.

2 1

linking query
by Sean Farrow 01 Feb '09

01 Feb '09

Hi: I've now got boost libraries compiled. The only other query I have is I have my visual studio project set up to use multi-threaded debug dll but when I build with boost filesystem it links the code in by default. How can I tell boost to use the dll version for debug and lib (static) for release? Sean.

1 0

[Smart Ptr] intrusive_ptr_add_ref(T * & p)
by Alexader 01 Feb '09

01 Feb '09

Looks like it is possible to define intrusive_ptr_add_ref as void intrusive_ptr_add_ref(T * & p) not as void intrusive_ptr_add_ref(T * p) Then, it is possilbe either to increase reference count as usually or to clone the object if it is in non-shareable state. Would this work ? Is it know use case, maintained by Smart Pointers library ?

1 0

error linking the boost.filesystem library
by Sean Farrow 01 Feb '09

01 Feb '09

Hi: When trying to build a probram with the boost.filesystem library, I get an lnk1104 using visual studio 8 (2005). The boost include and lib paths c:\program files\boost and c:\program files\boost\bin.v2 are in the default vc include and library paths respectively, the archive bit is set--this shouldn't make a difference as far as I know! Any one know why this error is ocuring? Cheers Sean.

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[Fusion] Sequence adapter
by Joel Falcou 01 Feb '09

01 Feb '09

Fusion provides supprot for thing like boost::tuple or boost::array to be treated as fusion sequence in runtime algorithm. Is there any meta-function that gives me the compile-time conversion or should I build them myself ? eg as_vector< array<int,6> >::type == vector<int,int,int,int,int,int> Thanks in advance -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

2 1

Calling a function in a defined time intervall
by Olivier Tournaire 01 Feb '09

01 Feb '09

Hi all, I would like to know how can I call a member function each x miliseconds, during a given time. Can any boost library help me for this task ? Regards, Olivier -- Olivier Tournaire MATIS - Institut Géographique National 73, Ave de Paris 94165 St Mandé cedex, France tel: (+33) 1 43 98 80 00 - 71 25 fax: (+33) 1 43 98 85 81

3 4

date-time library and checked iterators 2
by gast128 01 Feb '09

01 Feb '09

Dear all, I post half year ago about a problem in the Boost.DateTime library but never got an answer. So I try again: 'the date_facet::do_put_tm' fct. contains an illegal dereferncing in '&*a_format.begin()'. If the a_format string is empty VS2008 complains (and terminates) about illegal iterator dereference. I suspect though that VS2008 is right. Is it possible that this gets attention, or is something else wrong? Wkr, me

2 8

Cosmetic warning in gcc 4.3
by Joel Falcou 01 Feb '09

01 Feb '09

I foudn that the following lines int he following files generates a huge amount of spurious warning in gcc 4.3 with -Wall : /boost/math/special_functions/gamma.hpp line 1264: tgamma1pm1(T z, const Policy& /* pol */) /boost/function_types/detail/pp_retag_default_cc/preprocessed.hpp line 18 BOOST_STATIC_CONSTANT(bits_t, value = ( (::boost::function_types::detail::bits<Tag> ::value & 0x00008000 ) |( ::boost::function_types::detail::bits<RefTag> ::value & 802) )); /boost/function_types/detail/pp_tags/preprocessed.hpp line 56 BOOST_STATIC_CONSTANT(bits_t, combined_bits = (LHS_bits & ~RHS_mask) | RHS_bits ); The later was signaled as a ticket in trac but I wanted to know if it was fixed/merged in the upcoming 1.38. -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

2 1

Do "entire range" standard algorithms already exist
by Kirk Korver 01 Feb '09

01 Feb '09

Group, I recently found the boost::range library. It seems very useful. An annoyance that I have with STL algorithms is that they are very verbose. Most of the time I need to do something over the entire range. I'm sure I'm not alone here. At any rate, I can easily do this: template< typename Range, typename Pred > inline typename boost::range_iterator<Range>::type find_if( Range& c, Pred pred ) { return std::find_if( boost::begin( c ), boost::end( c ), pred ); } Which then allows me to do this: void foo() { typedef std::vector <int> V_INT; V_INT v; v.push_back(1); v.push_back(2); v.push_back(3); V_INT::iterator it = find_if(v, std::bind2nd(std::equal_to<int>(), 2)); } Perfect. Exactly what I want. Search the entire vector, and I give it a predicate. I could easily create these functions for copy_if, erase_if, find_if, and for_each. My question: Do I need to go ahead and create the tiny wrapper functions, or do they already exist somewhere in Boost? If they exist already, I prefer to use those. Thank you in advance, Kirk

4 3

[traits] Type of class of member function pointer
by Rutger ter Borg 01 Feb '09

01 Feb '09

Dear all, perhaps more out of exercise, but does any of you know whether it is possible to get to the type of the class of a member function pointer? I.e., to somehow get to type T in "R (T::*)()"? (in this particular case, a member function without arguments in class T returning R)? Thanks a lot, Rutger

3 4

[Interprocess] Unable to list created shared memory via ipcs command
by Leo Giannelli 31 Jan '09

31 Jan '09

Hello, I am a new user of the Boost Libraries. Currently, I tried the Boost.Interprocess source library with an example program which creates a shared memory segment and writes a vector into the shared memory. A receiver process attaches to the named shared memory segment and outputs the vector. This all works has advertized. The one issue is that whenever I try to list the shared memory segment via the ipcs -m command I do not see the shared memory created from the sender program. This is the code snippet which creates the shared memory: #include <boost/interprocess/managed_shared_memory.hpp> ...managed_shared_memory segment (create_only ,"MySharedMemory" //segment name ,65536); //segment size in bytes ... Note: The sender program is running for 5 minutes before terminating and removing the shared memory. The binaries were built with g++ version 3.4.6 20060404 (Red Hat 3.4.6-8) RedHat Linux 5: Kernal Version : uname -a Linux xxx 2.6.9-67.ELsmp #1 SMP Wed Nov 7 13:56:44 EST 2007 x86_64 x86_64 x86_64 GNU/Linux Best Regards, Leo -- Be Yourself @ mail.com! Choose From 200+ Email Addresses Get a Free Account at www.mail.com

2 1

[spirit2] where are the docs?
by Michael Marcin 31 Jan '09

31 Jan '09

I can't seem to find the spirit 2 documentation. Is there a copy online? -- Michael Marcin

2 2

Tree library?
by Germán Diago 31 Jan '09

31 Jan '09

Is there any library in preparation in boost to use tree data structures? If not, I would like to know where I can find a good implementation of any open source tree library. I found this one, but I'm not sure if it's good quality. It seems to be: http://www.aei.mpg.de/~peekas/tree/ Thanks for your time.

10 49

[gil] bad_cast exception
by Olivier Tournaire 30 Jan '09

30 Jan '09

Hi all, I am trying to use GIL and face a problem. Here is the code : namespace boost { namespace gil { /// Extension a GIL pour gerer les pixels "double" ... typedef pixel< double, boost::gil::gray_layout_t > gray64_pixel_t; typedef image< gray64_pixel_t, false > gray64_image_t; typedef image< gray64_pixel_t, true > gray64_planar_image_t; //typedef image_view< gray64_pixel_t > gray64_view_t; } } int main ( int argc , char **argv) { typedef boost::mpl::vector< boost::gil::gray8_image_t, boost::gil::gray16_image_t, boost::gil::gray32_image_t, //boost::gil::gray64_image_t, boost::gil::rgb8_image_t, boost::gil::rgb16_image_t, boost::gil::rgb32_image_t > my_img_types; typedef boost::mpl::vector< boost::gil::gray8_view_t, boost::gil::gray16_view_t, boost::gil::gray32_view_t, //boost::gil::gray64_view_t, boost::gil::rgb8_view_t, boost::gil::rgb16_view_t, boost::gil::rgb32_view_t > my_view_types; if ( argc < 4 ) { usage(); return 1; } std::string input_filename( argv[1] ); std::string output_filename( argv[3] ); int channel_index; try { channel_index = boost::lexical_cast<int>( argv[2] ); } catch( boost::bad_lexical_cast &e) { std::cout << "bad_lexical_cast exception : " << e.what() << std::endl; return 1; } boost::gil::any_image<my_img_types> runtime_image; boost::gil::any_image_view<my_view_types> runtime_view; try { boost::gil::jpeg_read_image( input_filename , runtime_image ); runtime_view = boost::gil::nth_channel_view( const_view(runtime_image) , channel_index ); boost::gil::jpeg_write_view( output_filename , runtime_view ); } catch( std::exception &e ) { std::cout << e.what() << std::endl; return 1; } return 0; } I get an exception on this line : runtime_view = boost::gil::nth_channel_view( const_view(runtime_image) , channel_index ); However, when I write : boost::gil::jpeg_write_view( output_filename , boost::gil::nth_channel_view( const_view(runtime_image) , channel_index ) ); everything goes well. Where is my mistake ? Best regards, Olivier -- Olivier Tournaire MATIS - Institut Géographique National 73, Ave de Paris 94165 St Mandé cedex, France tel: (+33) 1 43 98 80 00 - 71 25 fax: (+33) 1 43 98 85 81

2 7

Thread status
by Jens Luedicke 30 Jan '09

30 Jan '09

Hallo, how can I check if a given thread is runinng/finished/sleeping? Jens

3 4

Re: [Boost-users] RBGL use with BGL minCut() function
by Gianni Loiacono 30 Jan '09

30 Jan '09

Hi Mr. Sutton thanks for the answer. I didn't know what was **R :-D**. Now I have readed some links and I have understand that RBGL is not adapt for my project (into the file zip Win Binary I have seen a .dll file than I thought that I could use more libraries :)). My goal is to do multi minimum cuts (gomory hu tree algorithm: http://www.corelab.ntua.gr/~syrganis/sources/Gomory-Hu.pdf ). The min-cut BGL functions give out only the min-cut value, I want to know what edges were cut. Can you help me? Sorry for my english ;/ Thanks a lot for your time and for the help. Bye.

4 3

building 32 and 64-bit Boost on the same platform
by Damien Hocking 30 Jan '09

30 Jan '09

Hi all, I'm working on a cross-platform project that needs 32 and 64-bit Boost on Windows, Linux and OS X. I can happily build the individual versions on each platform, e.g. bjam --build-dir=./build64 --toolset=darwin address-model=64 architecture=x86 --build-type=complete stage for OS X, but is there a way to get the stage directory renamed to say stage 64 so I can batch all this up and build the 32 and 64-bit versions without any intervention by me? I can write shell or batch scripts to copy or rename the stage directory, but if there's an option in the build system I'd like to know about it. Thanks in advance. Damien

3 3

Flushing a filtering_ostreambuf
by jean-louis.a.leroy＠fortis.com 30 Jan '09

30 Jan '09

I have implemented a stream that sends output to the debugger (using OutputDebugString() in Windows): class debug_output_sink : public boost::iostreams::sink { public: debug_output_sink(int) { } std::streamsize write(const char* s, std::streamsize n); // also tried with: // struct category : boost::iostreams::sink::category, boost::iostreams::flushable_tag { }; // bool flush() { return true; } }; When I use it directly, flush() works fine: stream_buffer<debug_output_sink> debug_streambuf(debug_sink); ostream debug_stream(&debug_streambuf); debug_stream << "test\n"; debug_stream.flush(); // characters appear immediately However, when I put it in a filter, flushing the filter doesn't flush the stream: // scope { stream_buffer<debug_output_sink> debug_streambuf(debug_sink); ostream debug_stream(&debug_streambuf); filtering_ostreambuf filtering_buf; filtering_buf.push(debug_stream); ostream os(&filtering_buf); os << "test"; os.flush(); // nothing filtering_buf.pubsync(); // nothing either filtering_buf.strict_sync(); // still nothing } // characters appear at last ! What I am missing here? Thanks, Jean-Louis Leroy

2 1

enable_if for class members
by Christopher Jefferson 30 Jan '09

30 Jan '09

In a class, I want to have one member function which has different implementations depending on one of the template parameters. I tried to use enable_if template<bool b> struct foo { typename boost::enable_if_c<b, int>::type get_val( ) { return 2; } typename boost::disable_if_c<b, int>::type get_val() { return 3; } }; But when I use foo in code, it doesn't work, complaning that: error: no type named 'type' in 'struct boost::enable_if_c<true, int>' Am I not using enable_if in the correct way? Is there any easy way to do waht I'm trying to do? I used to do this by declaring an inner class and overloading that, but then it is necessary to pass in the class and the code looks very messy. Thanks, Chris

3 2