February 2004 - Boost-users - lists.preview.boost.org

regex_replace to replace a number?
by mike.duong＠adelphia.net 25 Feb '04

25 Feb '04

Hi, I am a newbie to regex. Can anyone please help? I am trying to replace $number with a number 2 but instead it looks for argument number 12. What is the format or escape sequence format_string variable needs to be? regex e("(\\$number)"); const char* format_string = "(?12)"; regex_replace(out, file_stream.begin(), file_stream.end(), e, format_string, match_default | format_all); Thanks, Mike

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regex_replace to replace a specify string
by mike.duong＠adelphia.net 24 Feb '04

24 Feb '04

Hi, Can someone please help? I would like to replace the match (*) with raw data. Is this possible? regex_replace(out, file_stream.begin(), file_stream.end(), my_regex, "(?12)", match_default | format_all); How can I replace the match with a number 2? I've tried difference combination of escape character before the 2 such as (?1\\d2) but it doesn't seems to work. Thanks, Mike

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boost::bind placeholders and MSVC .NET 2003 and .pch
by Vladimir Suhoy 24 Feb '04

24 Feb '04

I have linker errors using bind placeholders. The problem is when it is used in more than one .cpp file, and precompiled headers are on (as usual - created in stdafx.cpp and used in other modules) the linker says following: error LNK2005: "class boost::arg<1> `anonymous namespace'::_1" (?_1@?A0x51895292@@3V?$arg@$00@boost@@A) already defined in jc.obj When precompiled headers are off, everything works right. _________________________________________________________________ Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail

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Re: [Boost-users] Getting vertices names.
by Maxx Sloyko 24 Feb '04

24 Feb '04

Hi there! Here is my piece of code, where the error raises: void MyGraph::Load( string filename ) { using namespace boost; graph_traits<GraphvizDigraph>::vertex_iterator i; GraphvizDigraph g; read_graphviz(filename, g); graph_property<GraphvizDigraph, graph_name_t>::type& name = get_property( g, graph_name ); Name( name ); boost::property_map<boost::GraphvizDigraph, boost::vertex_attribute_t>::type& va = boost::get(boost::vertex_attribute, g); boost::property_map< GraphvizDigraph, vertex_name_t>::type& vn = get(vertex_name, g); /* First, lets load all needed properties for vertices */ for(i = vertices(g).first; i != vertices(g).second; ++i ) { map<string, string>& m = va[(*i)]; for( std::map<string, string>::const_iterator p_key = m.begin(); p_key != m.end(); ++p_key ) { std::cout<<vn[(*i)]<<endl; /* ^^^^ this is the line where the problem arises. he thing is to make the following line work (first argument is std::string ), but there was an error here and i decided to test like this. */ SetObjAttribute( vn[(*i)], const_cast<std::string&>(p_key->first), const_cast<std::string&>(p_key- >second) ); } } } Jeremy Siek <jsiek(a)osl.iu.edu>: > Hi Maxx, > > From what you've posted, I can't tell what the problem is. > If you post a short but complete program exhibiting the problem > I'll take a look. > > Cheers, > Jeremy > > On Feb 24, 2004, at 8:42 AM, Maxx Sloyko wrote: > > > Hi there! > > > > May be I'm asking something unbeleivably stupid, but anyway here is my > > problem. > > I need to get the names of all vertices in the graph (It is > > GraphvizDigraph), so > > ---------------------------------------------------- > > using namespace boost; > > property_map< GraphvizDigraph, > > vertex_name_t>::type& > > vn = get(vertex_name, g); > > graph_traits<GraphvizDigraph>::vertex_iterator i; > > > > for(i = vertices(g).first; i != vertices(g).second; ++i ) > > { > > std::cout<< vn[*i]<<endl; > > } > > ---------------------------------------------------- > > > > And here is the error I got: > > ---------------------------------------------------- > > c:\Documents and Settings\MAKC\My Documents\Visual Studio > > Projects\Graph\MyGraph.cpp(61) : error C2679: binary '<<' : no operator > > found which takes a right-hand operand of > > type > > 'boost::vec_adj_list_any_vertex_pa::bind_<Tag,Graph,Property>::value > > _type' (or there is no acceptable conversion) > > with > > [ > > Tag=boost::vertex_name_t, > > Graph=boost::detail::subgraph_any_pmap::bind_<boost:: > > vertex_name_t,boost: > > :GraphvizDigraph,boost::detail::vertex_property_map<boost:: > > GraphvizDigrap > > h,boost::vertex_name_t>::Property>::Graph, > > > > Property=boost::detail::vertex_property_map<boost::detail:: > > subgraph_any_p > > map::bind_<boost::vertex_name_t,boost::GraphvizDigraph,boost::detail:: > > ver > > tex_property_map<boost::GraphvizDigraph,boost::vertex_name_t>:: > > Property>: > > :Graph,boost::vertex_name_t>::Property > > ] > > ----------------------------------------------------- > > > > > > Since this code is almost "CopyPasted" from the library example, > > my beleif is that it should work. At what point I have to change my > > worldview? :) > > > > Thanks in advance. > > > > > > ------------------------------------- > > |your sincerely, Maxx, | > > | mailto:maxxua@pisem.net | > > ------------------------------------- > > _______________________________________________ > > Boost-users mailing list > > Boost-users(a)lists.boost.org > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > _______________________________________________ > Jeremy Siek <jsiek(a)osl.iu.edu> > http://www.osl.iu.edu/~jsiek > Ph.D. Student, Indiana University Bloomington > C++ Booster (http://www.boost.org) > Office phone: (812) 856-1820 > _______________________________________________ > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > ------------------------------------- |your sincerely, Maxx, | | mailto:maxxua@pisem.net | -------------------------------------

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Getting vertices names.
by Maxx Sloyko 24 Feb '04

24 Feb '04

Hi there! May be I'm asking something unbeleivably stupid, but anyway here is my problem. I need to get the names of all vertices in the graph (It is GraphvizDigraph), so ---------------------------------------------------- using namespace boost; property_map< GraphvizDigraph, vertex_name_t>::type& vn = get(vertex_name, g); graph_traits<GraphvizDigraph>::vertex_iterator i; for(i = vertices(g).first; i != vertices(g).second; ++i ) { std::cout<< vn[*i]<<endl; } ---------------------------------------------------- And here is the error I got: ---------------------------------------------------- c:\Documents and Settings\MAKC\My Documents\Visual Studio Projects\Graph\MyGraph.cpp(61) : error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'boost::vec_adj_list_any_vertex_pa::bind_<Tag,Graph,Property>::value _type' (or there is no acceptable conversion) with [ Tag=boost::vertex_name_t, Graph=boost::detail::subgraph_any_pmap::bind_<boost::vertex_name_t,boost: :GraphvizDigraph,boost::detail::vertex_property_map<boost::GraphvizDigrap h,boost::vertex_name_t>::Property>::Graph, Property=boost::detail::vertex_property_map<boost::detail::subgraph_any_p map::bind_<boost::vertex_name_t,boost::GraphvizDigraph,boost::detail::ver tex_property_map<boost::GraphvizDigraph,boost::vertex_name_t>::Property>: :Graph,boost::vertex_name_t>::Property ] ----------------------------------------------------- Since this code is almost "CopyPasted" from the library example, my beleif is that it should work. At what point I have to change my worldview? :) Thanks in advance. ------------------------------------- |your sincerely, Maxx, | | mailto:maxxua@pisem.net | -------------------------------------

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Streaming boost::optional yields inconsistent output in gcc 3.2.3
by Eelis van der Weegen 24 Feb '04

24 Feb '04

Hi, I defined the following operator to stream optional<char>'s: std::ostream & operator<< (std::ostream & os, boost::optional<char> const & op) { if (op) os << *op; else os << '_'; return os; } Now, when I use: boost::optional<char> a ('a'); std::cout << a; 'a' is printed like I expected. However, when I use: std::ostream_iterator<boost::optional<char> > oi (std::cout); *oi = a; '1' is printed and my operator is apparently ignored (I expected another 'a'). Is this a gcc (3.2.3) issue or a boost issue? And in any case: is there a workaround? Thanks, Eelis

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Re: [Boost-users] Boost Newbie: Boost Libraries notincluded .....Linker Error
by Mohammed Abbas 24 Feb '04

24 Feb '04

Oooops thanks for the thought: Im running gcc on Windows XP Home Edition. -- --------- Original Message --------- DATE: Mon, 23 Feb 2004 07:50:23 From: Darren Cook <darren(a)dcook.org> To: Boost Users mailing list <boost-users(a)lists.boost.org> Cc: >> Could anyone send me a copy of the library files that aer produced... > >You didn't say which platform. > >>>I had built the Boost Libraries and was expecting that the sample > >>simple_ls program to work. Unfortunately as I compiled it I > >>had received a million plus errors due to the Linker Error. > >>.... > >>P.S. The Library folder for Boost is Empty and I includeded the Boost >Include Directory in the gcc path. > >If you post the first 4-5 and last 4-5 lines of errors (and show the full >compiler command you are using) someone may be able to help then. > >Darren > > >_______________________________________________ >Boost-users mailing list >Boost-users(a)lists.boost.org >http://lists.boost.org/mailman/listinfo.cgi/boost-users > ____________________________________________________________ Find what you are looking for with the Lycos Yellow Pages http://r.lycos.com/r/yp_emailfooter/http://yellowpages.lycos.com/default.as…

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Iterator adaptor interoperability
by Kris Braun 24 Feb '04

24 Feb '04

Hello, I've spent the day trying to get my iterators working after upgrading to 1.31.0. I'm almost there, but I can't seem to get const and non-const versions to compare with each other. I've tried about everything I can think of, so I'll just post a minimal test that fails in hopes that someone can see my mistake: #include <iostream> #include <list> #include <boost/iterator/transform_iterator.hpp> template< class Type > struct do_nothing { typedef Type result_type; result_type operator( )( const Type& t ) { return t; } }; template< class Iterator > class simple_iterator : public boost::transform_iterator< do_nothing< typename Iterator::value_type >, Iterator > { private: typedef boost::transform_iterator< do_nothing< typename Iterator::value_type >, Iterator > super_t; public: simple_iterator( void ) { } simple_iterator( Iterator iter ) : super_t( iter ) { } template< class Iterator2 > simple_iterator( const simple_iterator< Iterator2 >& iter ) : super_t( iter.base( ) ) { } }; typedef std::list< int > ListType; typedef simple_iterator< ListType::iterator > iterator; typedef simple_iterator< ListType::const_iterator > const_iterator; struct Foo { iterator begin( void ) { return iterator( m.begin( ) ); } const_iterator end( void ) const { return const_iterator( m.end( ) ); } ListType m; }; void foo( void ) { Foo f; for( iterator i = f.begin( ); i != f.end( ); ++i ) { } } which on VC7.1 yield src\util\test.cpp(53) : error C2678: binary '!=' : no operator found which takes a left-hand operand of type 'iterator' (or there is no acceptable conversion) Any help would be much appreciated! Cheers, Kris __________________________________ Do you Yahoo!? Yahoo! Mail SpamGuard - Read only the mail you want. http://antispam.yahoo.com/tools

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Problem building boost 1.31 on True64 Unix
by Wenzel, Hans 23 Feb '04

23 Feb '04

Hi all, I'm trying to build the complete boost 1.31 on a True64 Unix V5.1A machine using the Compaq C++ V6.5-014 compiler. After invoking bjam, the compiler hangs on the last command seen below. What can I do? cxx -ptr "bin/boost/libs/filesystem/build/libboost_filesystem.so/tru64cxx65/r elease"/cxx_repository -noimplicit_include -c -std strict_ansi -nopure_cname -m sg_display_number -msg_disable 186,450,1115 -DNDEBUG -DNDEBUG -DBOOST_FILESYSTE M_DYN_LINK=1 -O2 -inline all -I"bin/boost/libs/filesystem/build" -I"/usr/loc al/boost_1_31_0" -I"/usr/local/boost_1_31_0" -o "bin/boost/libs/filesystem/bui ld/libboost_filesystem.so/tru64cxx65/release/operations_posix_windows.o" "/usr/ local/boost_1_31_0/libs/filesystem/build/../src/operations_posix_windows.cpp " Best regards HansW

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Re: [Boost-users] Boost Newbie: Boost Libraries not included .....Linker Error
by Mohammed Abbas 22 Feb '04

22 Feb '04

Could anyone send me a copy of the library files that aer produced when building the boost libraries. Im not getting anything in my directory and Im already late in my project proposal. Yours MJ --------- Original Message --------- DATE: Fri, 20 Feb 2004 14:03:27 From: "Mohammed Abbas" <mjabbas(a)lycos.com> To: boost-users(a)lists.boost.org Cc: >Hi, > >Im a newbie in C++ just barely getting to grips with the Boost Libraries. I had built the Boost Libraries and was expecting that the sample simple_ls program to work. Unfortunately as I compiled it I had received a million plus errors due to the Linker Error. > >Please tell me whats wrong???????????? > >P.S. The Library folder for Boost is Empty and I includeded the Boost Include Directory in the gcc path. > >Yours, > >MJ > > >____________________________________________________________ >Find what you are looking for with the Lycos Yellow Pages >http://r.lycos.com/r/yp_emailfooter/http://yellowpages.lycos.com/default.as… >_______________________________________________ >Boost-users mailing list >Boost-users(a)lists.boost.org >http://lists.boost.org/mailman/listinfo.cgi/boost-users > ____________________________________________________________ Find what you are looking for with the Lycos Yellow Pages http://r.lycos.com/r/yp_emailfooter/http://yellowpages.lycos.com/default.as…

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tokenizer and wstring with VC7.1
by Douglas G. Hanley 22 Feb '04

22 Feb '04

Has anybody managed to get tokenizer working for wide characters with VC7.1 (boost version 1.31.0)? The following example works fine... typedef tokenizer<char_separator<std::string::value_type>, std::string::const_iterator, std::string> MyTokenizer; const char_separator<std::string::value_type> sep("a"); MyTokenizer token(std::string("abacadaeafag"), sep); for (MyTokenizer::const_iterator it = token.begin(); it != token.end(); ++it) { std::cout << *it; } ...while the following example produces no output... typedef tokenizer<char_separator<std::wstring::value_type>, std::wstring::const_iterator, std::wstring> MyTokenizer; const char_separator<std::wstring::value_type> sep(L"a"); MyTokenizer token(std::wstring(L"abacadaeafag"), sep); for (MyTokenizer::const_iterator it = token.begin(); it != token.end(); ++it) { std::wcout << *it; } Cheers, Douglas.

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Tokenizer Problem
by Thomas Johnson 22 Feb '04

22 Feb '04

Can anyone explain to me why the code below prints: Token: A1B21 Token: A1B Token: : Token: 12 Instead of printing: Token: A1B2 Token: : Token: 12 Token: A1B Token: : Token: 12 Using boost 1.31.0 Thanks! ---Cut here--- #include <boost/tokenizer.hpp> #include <iostream> int main() { boost::char_separator<char> sep("", ":", boost::keep_empty_tokens); boost::tokenizer< boost::char_separator<char> > stringTok(std::string("A1B2:12"),sep); boost::tokenizer< boost::char_separator<char> >::iterator tokIter=stringTok.begin(); while(tokIter!=stringTok.end()) { std::cout << "Token: " << (*tokIter) << "\n"; tokIter++; } boost::tokenizer< boost::char_separator<char> > stringTok2(std::string("A1B:12"),sep); boost::tokenizer< boost::char_separator<char> >::iterator tokIter2=stringTok2.begin(); while(tokIter2!=stringTok2.end()) { std::cout << "Token: " << (*tokIter2) << "\n"; tokIter2++; } } ---Cut Here--- -- Thomas Johnson <thomas(a)unifiedconsulting.com>

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Boost Newbie: Boost Libraries not included ..... Linker Error
by Mohammed Abbas 20 Feb '04

20 Feb '04

Hi, Im a newbie in C++ just barely getting to grips with the Boost Libraries. I had built the Boost Libraries and was expecting that the sample simple_ls program to work. Unfortunately as I compiled it I had received a million plus errors due to the Linker Error. Please tell me whats wrong???????????? P.S. The Library folder for Boost is Empty and I includeded the Boost Include Directory in the gcc path. Yours, MJ ____________________________________________________________ Find what you are looking for with the Lycos Yellow Pages http://r.lycos.com/r/yp_emailfooter/http://yellowpages.lycos.com/default.as…

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Semaphore and barriers for boost-threads?
by Craig Rodrigues 20 Feb '04

20 Feb '04

Hi, I am new to Boost, and like what I see. I hope to be able to use more Boost libraries in the C++ projects that I work on. Would it be a good thing to add semaphore and barrier classes to Boost Threads? For semaphores, having something analogous to the POSIX functions sem_wait() and sem_post() would be nice. For barriers, having something analogous to pthread_barrier_wait() would be nice. It is not very hard to roll your own versions of these primitives using boost::condition and boost::mutex classes, but it would be nice to have them in a library. Any opinions? Thanks. -- Craig Rodrigues http://crodrigues.org rodrigc(a)crodrigues.org

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Counting matches with Regex V4
by john.wismar＠autozone.com 20 Feb '04

20 Feb '04

<Using VC7.0> I'm converting to V4 of Regex, and I thought I might be able to count regex matches using this snippet: boost::regex e; std::string::const_iterator first, last; //Initialize first, last boost::sregex_iterator itBegin(first, last, e) boost::sregex_iterator itEnd; ptrdiff_t pd = std::distance(itBegin, itEnd); I get these errors: xutility(312) : error C2665: 'std::_Iter_cat' : none of the 12 overloads can convert parameter 1 from type 'boost::sregex_iterator' xutility(127): could be 'std::_Int_iterator_tag std:: _Iter_cat(std::_Bool)' xutility(133): or 'std::_Int_iterator_tag std:: _Iter_cat(char)' xutility(139): or 'std::_Int_iterator_tag std:: _Iter_cat(signed char)' xutility(145): or 'std::_Int_iterator_tag std:: _Iter_cat(unsigned char)' xutility(151): or 'std::_Int_iterator_tag std:: _Iter_cat(short)' xutility(157): or 'std::_Int_iterator_tag std:: _Iter_cat(unsigned short)' xutility(163): or 'std::_Int_iterator_tag std:: _Iter_cat(int)' xutility(169): or 'std::_Int_iterator_tag std:: _Iter_cat(unsigned int)' xutility(175): or 'std::_Int_iterator_tag std:: _Iter_cat(long)' xutility(181): or 'std::_Int_iterator_tag std:: _Iter_cat(unsigned long)' xutility(188): or 'std::_Int_iterator_tag std::_Iter_cat (__int64)' xutility(194): or 'std::_Int_iterator_tag std:: _Iter_cat(unsigned __int64)' while trying to match the argument list '(boost::sregex_iterator)' myfile.h(47) : see reference to function template instantiation 'ptrdiff_t std::distance(_InIt,boost::sregex_iterator)' being compiled with [ _InIt=boost::sregex_iterator ] Anyone have any thoughts? Is it a VC7.0 issue? Is there a better or different way of doing the same thing? -------------------------------- John Wismar jwismar(a)midsouth.rr.com ------------------------------------------------------------------------ The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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[Graph] What can I do with null_vertex?
by Douglas Gregor 20 Feb '04

20 Feb '04

There are no semantics for null_vertex. I assume I can copy it, but can I compare it against other vertex descriptors via == and !=? Is it always different from "real" vertex descriptors? Doug

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Determining offset of regex syntax errors
by Keith MacDonald 20 Feb '04

20 Feb '04

Members of class reg_expression know where they are up to while compiling, but don't include that information when they throw. It can be pretty daunting to get the "Invalid regular expression" error message, with no indication of where to start looking, so I'd like to be more helpful. Given the character offset from the start of the RE, I can put the cursor there. Any suggestions as to how to obtain that information? Thanks, Keith MacDonald

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Redirecting the detailed test report
by Hermann Oliveira Rodrigues 20 Feb '04

20 Feb '04

Hi, Recently we have decided to use the Boost Test libraries to provide automated tests to our project. To help with the test result visualization, we created an utility to generate HTML pages from Boost test reports (as generated by -- report_level=detailed). In the begining of implementation, the amount of tests was small and we could just cut-and-paste the test report to a file used as the input of out in-house HTML generator. Now, the amount of tests increased and cutting-and-pasting the report become a pain. So the question: How can we send the test report to a separated file? We used unit_test_log::instance().set_log_stream( stream ) in the definition of test_suite* init_unit_test_suite( int argc, char* argv[] ) to redirect the test log and it worked fine. However, unit_test_result::instance().detailed_report( stream ) can not be used in the same way. We can not simply redirect the test output to a file (using ">") because our application prints lots of information during execution and is pretty hard to change this behaviour. Thanks in advance.

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Overloading New and Delete to track memory in shared_ptr.
by Joshua Little 19 Feb '04

19 Feb '04

Hi again, Well I'm making pretty good progress in learning proper way to use shared_ptr's but I'm still a little nervous about leaking memory, especially if I manage to do something I'm not supposed to do and don't recognize that a memory leak may be occuring. I've used the overloading new/delete before to help track memory leaks and I was wondering if that would be possible with shared_ptrs. I tried my old header files with and saw tons of leaks but I think its because my New that I use logs the creation to a Tracer class but since the Delete happens in the shared_ptr, its not using the overloaded Delete that removes stuff from the tracer when its deleted. I've looked around and found some examples of making a custom deleter to pass into the shared ptr when creating a new shared_ptr which should work but I have some worries about it. I'm not quite sure what the recommended way of doing this would be. About the only thing I can think of would be to have two different deleters which would be conditionally compiled something like this : //Overloaded New to log allocation to a tracer, theres a define to add the file and line number to the new call #ifndef NDEBUG void * operator new (unsigned int size, char const * file, int line) { void * p = new (size); if (Tracer::Ready) NewTrace.Add (p, file, line); return p; } struct deleter { void operator() (void * p) const { if (Tracer::Ready) NewTrace.Remove(p); delete p; } } #else struct deleter { void operator() (void * p) const { delete p; } } #endif //NewTrace is an extern'd object in the Main.cpp file So then I'd pass in the deleter to the shared_ptr and then whichever deleter was defined would be passed into the shared_ptr. I'm kinda cobbling together a few different things I've seen but I think that with this I could include the header file in the .cpp file of any class that I want to track the memory of and then just make sure I send in the deleter when I reset or make a new shared ptr. For instance in my LoggerFactory.cpp file : #include "../include/Logger.hpp" #include "../include/LoggerFactory.hpp" #include "../include/dbnew.hpp" LoggerMap LoggerFactory::loggers; boost::shared_ptr<Logger> LoggerFactory::getInstance(std::string& logger) { boost::shared_ptr<Logger>& TheLoggerRef = loggers[logger]; if(!TheLoggerRef.get()) TheLoggerRef.reset(new Logger(logger),deleter()); return TheLoggerRef; } So then the dbnew would define the deleter to use for the Logger object, if it was a debug build it would also create the overloaded new operator, define the _FILE_ and _LINE_ macros to send into the new New operator. And if its not the debug build then essentially the normal deleter is given to the shared_ptr and everything procedes as normal. Is this a good way to go about adding memory leak checking? I've looked for a new memory leak checkers like valgrind but thats only available on Linux and I'm stuck on windows.. and all the memory checkers I've been able to find only support VC++ or borland and I use gcc. So I would like a nice simple way that I can drop right in, which is what I'm going for with the overloading new and the custom deleter. Joshua.

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Concurrency support based on Boost.Threads
by Slawomir Lisznianski 19 Feb '04

19 Feb '04

License: Public Domain URL: http://www.rhapsodia.org Depends on: Boost, STL Code maturity: Beta Target platform: Any with C++ compiler. C++ compilers verified to work on: GNU g++ 3.2.x, Visual C++ 6 Service Pack 5 Description: Rhapsodia is a collection of header files implementing commonly used classes in concurrent C++ programming. Library mainly consists of implementations of: - Channel (bounded, unbounded and priority queue), - Barrier (multi-party synchronization) - Executor (replacement for direct use of thread creation and management API). Your critiques, suggestions or usage questions are much welcomed. Slawomir Lisznianski; [ www.rhapsodia.org ]

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RE: [Boost-users] Mathematical expressions with containers
by Hurd, Matthew 19 Feb '04

19 Feb '04

> Russell Hind > Subject: [Boost-users] Mathematical expressions with containers > > Currently I'm doing more and more mathematical calculations on > containers, and wondered if there is any library out there that allows > containers to be placed in expressions without having to use > transform/for_each etc. > > e.g. > > std::vector<std::complex<double> > V1; > std::vector<std::complex<double> > V2; > double C1, C2; > > ... > > std::vector<std::complex<double> > Result; > > Result = C1 + V2 / (V1 * C2); > > while would be equivalent to (assuming Result has been resized) > > (I'm currently using a mixture of transforms and spirit::phoenix > (because lambda doesn't work with my compiler)) > > transform(V1.begin(), V1.end(), V2.begin(), > Result.begin(), > C1 + phoenix::arg2 / (phoenix::arg1 * C2)); > > Or something to this effect that will aid with this. > > Cheers > > Russell Seems to my quick glance you are asking for some vector operations. Have you looked at boost's ublas? Regards, Matt Hurd. IMPORTANT: The information contained in this email and/or its attachments is confidential. If you are not the intended recipient, please notify the sender immediately by reply and immediately delete this message and all its attachments. Any review, use, reproduction, disclosure or dissemination of this message or any attachment by an unintended recipient is strictly prohibited. Neither this message nor any attachment is intended as or should be construed as an offer, solicitation or recommendation to buy or sell any security or other financial instrument. Neither the sender, his or her employer nor any of their respective affiliates makes any warranties as to the completeness or accuracy of any of the information contained herein or that this message or any of its attachments is free of viruses.

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Any one used boost with comeau c++ compiler for visual c++.net 2003?
by Ben Polen 18 Feb '04

18 Feb '04

To the community; I'm thinking of geting comeau computing's c++ frontend for visual c++.net 2003. I was wondering if anyone has experience using those two programs in conjunction with the boost libraries. In viewing the regression test, I was also wondering why Comeau doesn't seem to compile at a rate of 100% with boost. Is that due to Comeau unconformance, boost unconformance or problems with the c++ backend program, vc 7.1, gcc 3.2 ect. Anyone have any clues? Thanks Ben _________________________________________________________________ Stay informed on Election 2004 and the race to Super Tuesday. http://special.msn.com/msn/election2004.armx

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RE: [Boost-users] Trouble linking regex library on Solaris machine
by Ben Hutchings 18 Feb '04

18 Feb '04

Justin Adam Miller <millerj(a)wam.umd.edu> wrote: > Howdy. As I am only interested in using the regex library right now, I > followed the instructions for building that library only, using dmake. > Compilation went fine. When I tried using the library in a little test > program with the command: > > g++ regextest.cxx -I./boost_1_31_0 > -L./boost_1_31_0/libs/regex/build/sunpro -lboost_regex -o > regextest.cxx > > I get many undefined symbol errors. If requested, I can provide the > entire error output. It looks like you are trying to use the wrong library. SunPro refers to the Sun C++ compiler and tools whereas you are using GNU C++. You have to build the library and application with the same compiler.

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Trouble linking regex library on Solaris machine
by Justin Adam Miller 18 Feb '04

18 Feb '04

Howdy. As I am only interested in using the regex library right now, I followed the instructions for building that library only, using dmake. Compilation went fine. When I tried using the library in a little test program with the command: g++ regextest.cxx -I./boost_1_31_0 -L./boost_1_31_0/libs/regex/build/sunpro -lboost_regex -o regextest.cxx I get many undefined symbol errors. If requested, I can provide the entire error output. Justin Miller

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RE: [Boost-users] Re: Semaphore and barriers for boost-threads?
by Ben Hutchings 18 Feb '04

18 Feb '04

Craig Rodrigues <rodrigc(a)crodrigues.org> wrote: > It is possible to implement semaphore's with mutexes and > condition variables. I looked at the source code for > FreeBSD 5.2's implementation of semaphores to see how this was > done: > > http://www.freebsd.org/cgi/cvsweb.cgi/~checkout~/src/lib/libpthread/thre ad/thr_sem.c > > I even took a whack at writing one based on Boost (it may be buggy): > > #include <boost/thread.hpp> > #include <boost/thread/mutex.hpp> > > struct mysem { > mysem(unsigned int count): count_(count) {} > > void post() { > boost::mutex::scoped_lock l(sem_mutex_); > ++count_; > sem_cond_.notify_all(); notify_one() should be safe and more efficient here, because any of the waiters can be satisfied by the change you have made. Use notify_all() where waiters are waiting for different conditions on the same condition variable. (I'm not sure I expressed that exactly correctly - can anyone improve on that?) > } > > void wait() { > boost::mutex::scoped_lock l(sem_mutex_); > for(;;) { > > if( count_ == 0 ) sem_cond_.wait(l); This is wrong - you must always use while rather than if to test the inverse of the condition you are waiting for because it is possible that the condition is no longer true when wait() returns. (There is also a function template for wait() that tests a predicate for you.) It is even possible on some systems for wait() to return even though no-one called notify_one() or notify_all(). > else { --count_; break; } > } > } > > private: > unsigned int count_; > boost::mutex sem_mutex_; > boost::condition sem_cond_; > }; > > > What kinds of things can go wrong if I use this class? <snip> The other potential problem I see is overflow of count_, but it is exceedingly unlikely that you will be able to create enough threads to cause that.

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