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enable_if question
by Agoston Bejo 13 Jun '04

13 Jun '04

Hi, I understand that by using enable_if the following way: template <class T> T foo(T t, typename enable_if<boost::is_arithmetic<T> >::type* dummy = 0); I can include/exclude the appropriate function overloads. When I write: template<class T> T foo(T t, typename enable_if<[condition1]>::type* dummy = 0, typename enable_if<[condition2]>::type* dummy = 0); Does this mean an AND-relationship between condition1 and condition2? (So that a particular overload is enabled if and only if both conditions evaluate to true?) Thx, Gus

3 2

Dynamic bitset help
by Michael Short 13 Jun '04

13 Jun '04

Hello Has anyone got a few good examples of the dynamic bitset been used with member functions like append and block type? If so could you please send in some thanks. Michael

1 0

regex v4: regex_replace fails on trivial case
by Watermann Bernd (TCO/A) 12 Jun '04

12 Jun '04

Hi all, regex_replace("XX",regex("X", boost::regex::literal), "Y") returns "YXY" instead of "YY" whereas the (even more) trivial case regex_replace("X",regex("X", boost::regex::literal), "Y") returns "Y" as expected. I am using boost_1_31_0 compiled with VC6(SP5). In addition, I have applied the patches from the package boost-1.31.0-regex-patch-20040503. What is going wrong here? Bernd

2 1

newbie question: missing libs ?
by Randy.Ormond＠ngc.com 11 Jun '04

11 Jun '04

After building Boost 1.31.0 on Linux and on Irix, I expected to see a smart pointer library, something like libboost_smart_ptr-gcc-mt.so If fact, it looks like only date_time, filesystem, prg_exec, regex, signals, test_exec_monitor, thread, and unit_test_framework were built. I didn't see any error messages. Did I do something wrong? Thanks, Randy

2 1

Additional boost resources
by Agoston Bejo 11 Jun '04

11 Jun '04

Hi, do you know about any additional books, tutorials, etc. about boost on the net apart from the boost documentation itself? Any links / titles are welcome. Thx, Gus

2 1

problems using shared_ptr in threads
by Tristan King 11 Jun '04

11 Jun '04

Hi, I'm having trouble getting shared_ptr objects and threads to work in harmony. It may just be that i don't know enough about threads to solve this, but i'm getting undefined behaviour in the code posted at the end of this mail. i'm not worried about the order that the threads run in (as this is just an example of the problem i'm having in a simple multi-threaded web server i'm working on), but it seems like the shared_ptr object may be getting deleted before the last thread gets to execute. i.e. some sample output i'm getting is 0 1 3 4 -572662307 and 1 2 3 3 -572662307 i think i'm probably missing some mutex's or something, but i can't figure it out can anyone give me any pointers on how to get around this problem? thanks in advance --Tristan #include <iostream> #ifdef _MSC_VER #pragma warning(push, 1) #endif #include <boost/thread.hpp> #include <boost/shared_ptr.hpp> #ifdef _MSC_VER #pragma warning(pop) #endif struct simple_thread : public boost::noncopyable { simple_thread( boost::shared_ptr<int> i ) : m_i( i ) {} void operator( )( ) { std::cout << (*m_i) << std::endl; } boost::shared_ptr<int> m_i; }; int main( ) { boost::thread_group threads; for ( int i = 0 ; i < 5 ; ++i ) { boost::shared_ptr<int> p( new int(i) ); simple_thread trd( p ); threads.create_thread( boost::ref( trd ) ); }; threads.join_all( ); return 0; }

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link problems with boost_regex on Solaris
by Drew Lowry 09 Jun '04

09 Jun '04

I'm using boost_regex 1.28.0 with STLport 4.5.3 on Solaris using Forte compiler. When I build with -g option, it fails at linkage with the following errors ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(OhCenAP7d5aN-_Bfr3wh.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(J-U5NXbbfexb9iPLelyN.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(5cVinizdRsfQ1ujqbKlp.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(TbU7jVI0o3rCSz-c48HV.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(Zi2bUcR97vUxCHzFzV0a.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(aTM7t-gA2lwhiyP5RH3P.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(OkRWOOTWnnv97gH0a9t_.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../../packages/boost_1_28_0/sparc-solaris/libboost_regex_mt.a(hKZggW9H89qzPd1td_2e.o) ild: (undefined symbol) boost::detail::allocator<unsigned char>::allocator<char>#Nvariant 1(const boost::detail::allocator<__type_1>&) -- referenced in the text segment of ../../../engine/lib/sparc-solaris/ Any idea what's going on? Everything works fine without -g option. ____________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html

2 3

Problem compiling Threading lib on Linux
by Damien McGivern 09 Jun '04

09 Jun '04

Hi, I've been developing some code on Windows using Boost threads which works fine. I'm porting it to Linux and am having problems compiling the Boost Threading library. I'm running Linux Mandrake 10 Community Edition and have attached the output I get when running bjam. I don't actually have bjam included in the PATH enviroment variable as I'm not sure how to do this in Linux so I just copied the bjam exe into the thread build directory - I doubt it but could this be the cause of the problem? Any help on how to solve this would be much appreciated. Cheers Damien ____________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html [damien@tux build]$ ./bjam "-sTOOLS=gcc" ...patience... ...found 367 targets... ...updating 39 targets... MkDir1 ../../../libs/thread/build/bin-stage MkDir1 ../../../bin MkDir1 ../../../bin/boost MkDir1 ../../../bin/boost/libs MkDir1 ../../../bin/boost/libs/thread MkDir1 ../../../bin/boost/libs/thread/build MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/condition.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/mutex.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/recursive_mutex.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/thread.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/tss.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/xtime.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/once.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/exceptions.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/threadmon.o gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31d.so ln: creating symbolic link `../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31d.so' to `libboost_thread-gcc-mt-d-1_31d.so.1.31.0': Operation not permitted LD_LIBRARY_PATH=../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi:$LD_LIBRARY_PATH export LD_LIBRARY_PATH g++ -g -pthread -fPIC -shared -o "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31d.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/condition.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/recursive_mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/thread.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/tss.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/xtime.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/once.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/exceptions.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/threadmon.o" -lrt -Wl,-rpath-link,. -Wl,-soname,libboost_thread-gcc-mt-d-1_31d.so.1.31.0 ln -fs "libboost_thread-gcc-mt-d-1_31d.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31d.so" ...failed gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31d.so... ...skipped <@boost!libs!thread!build!bin-stage>libboost_thread-gcc-mt-d-1_31d.so for lack of <@boost!libs!thread!build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi>libboost_thread-gcc-mt-d-1_31d.so... FileClone ../../../libs/thread/build/bin-stage/libboost_thread-gcc-mt-d-1_31d.so.1.31.0 MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true MkDir1 ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/condition.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/mutex.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/recursive_mutex.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/thread.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/tss.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/xtime.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/once.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/exceptions.o gcc-C++-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/threadmon.o gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-1_31.so ln: creating symbolic link `../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-1_31.so' to `libboost_thread-gcc-mt-1_31.so.1.31.0': Operation not permitted LD_LIBRARY_PATH=../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi:$LD_LIBRARY_PATH export LD_LIBRARY_PATH g++ -pthread -s -fPIC -shared -o "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-1_31.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/condition.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/recursive_mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/thread.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/tss.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/xtime.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/once.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/exceptions.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/threadmon.o" -lrt -Wl,-rpath-link,. -Wl,-soname,libboost_thread-gcc-mt-1_31.so.1.31.0 ln -fs "libboost_thread-gcc-mt-1_31.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-1_31.so" ...failed gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-1_31.so... ...skipped <@boost!libs!thread!build!bin-stage>libboost_thread-gcc-mt-1_31.so for lack of <@boost!libs!thread!build/libboost_thread.so/gcc/release/shared-linkable-true/threading-multi>libboost_thread-gcc-mt-1_31.so... FileClone ../../../libs/thread/build/bin-stage/libboost_thread-gcc-mt-1_31.so.1.31.0 gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31.so ln: creating symbolic link `../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31.so' to `libboost_thread-gcc-mt-d-1_31.so.1.31.0': Operation not permitted LD_LIBRARY_PATH=../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi:$LD_LIBRARY_PATH export LD_LIBRARY_PATH g++ -g -pthread -fPIC -shared -o "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/condition.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/recursive_mutex.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/thread.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/tss.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/xtime.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/once.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/exceptions.o" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/threadmon.o" -lrt -Wl,-rpath-link,. -Wl,-soname,libboost_thread-gcc-mt-d-1_31.so.1.31.0 ln -fs "libboost_thread-gcc-mt-d-1_31.so.1.31.0" "../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31.so" ...failed gcc-Link-action ../../../bin/boost/libs/thread/build/libboost_thread.so/gcc/debug/shared-linkable-true/threading-multi/libboost_thread-gcc-mt-d-1_31.so... ...failed updating 3 targets... ...skipped 2 targets... ...updated 34 targets...

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BGL: Internal Compiler Error with VC++ 7.1
by Finnegan Southey 09 Jun '04

09 Jun '04

Hi, I'm getting the following error trying to iterate over adjacent vertices in boost_1_31 with VC++ 7.1: c:\boost_1_31_0\boost\mpl\aux_\preprocessed\plain\apply.hpp(50) : fatal error C1001: INTERNAL COMPILER ERROR (compiler file 'msc1.cpp', line 2701) I have noticed other similar problems reported in the list archive along with a request for a short example. Any advice would be appreciated. The following example demonstrates the problem, sufficiently briefly, I hope. -------------- CUT ------------------------------------------- #include <boost/graph/graph_traits.hpp> #include <boost/graph/adjacency_list.hpp> typedef boost::property<boost::edge_weight_t, int> LocationEdgeProperty; typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::undirectedS, boost::no_property, LocationEdgeProperty> LocationGraph; typedef boost::graph_traits<LocationGraph>::vertex_descriptor VertexDescriptor; typedef boost::graph_traits<LocationGraph>::adjacency_iterator AdjacencyIterator; void test() { LocationGraph graph; VertexDescriptor current = 0; std::pair<AdjacencyIterator, AdjacencyIterator> neighbourRange = boost::adjacent_vertices(current, graph); // ICE here for (; neighbourRange.first != neighbourRange.second; neighbourRange.first++) { } } -------------- CUT ------------------------------------------- Regards, Finnegan

1 0

Query re a Boost calculus library
by Andy Elvey 08 Jun '04

08 Jun '04

Hi everyone - I'm a newcomer to this list (but have used Boost Spirit for a long time). I've looked through the various Boost libraries and have noticed that there seems to be one area of mathematics that isn't covered by the existing libraries : calculus (derivatives, integrals). So, my question is - is there a reason for this, or is it just that a suitable library for inclusion hasn't appeared yet? ( I'm aware of a possible one that could be put forward as a candidate, but I don't know if it's "OK" for me to suggest a library ). Many thanks in advance. - Andy

2 2

RE: [Boost-users] enable_if question
by Hurd, Matthew 08 Jun '04

08 Jun '04

D'oh. Thanks Jaakko. Regards, Matt Hurd. _______________ Matt Hurd +61.2.8226.5029 hurdm(a)sig.com Susquehanna _______________ > bounces(a)lists.boost.org] On Behalf Of jajarvi > Subject: Re: [Boost-users] enable_if question > > On Jun 7, 2004, at 7:11 PM, Hurd, Matthew wrote: > > > > SFINAE does not kick in, because the condition > (is_arithmetic<std::string>::value) is not dependent on any template > arguments. > > Cheers, Jaakko > 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.

1 0

enable_if question
by Hurd, Matthew 08 Jun '04

08 Jun '04

I'm just trying to play with enable_if and learn something. I just mean to replace this template method's code: template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { if ( boost::is_arithmetic<std::string>::value ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } else { exchange_code<false>( new_exchange_code); } } With this: template< bool > typename boost::enable_if_c< boost::is_arithmetic<std::string>::value, void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } template< bool > typename boost::disable_if_c< boost::is_arithmetic<std::string>::value , void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { exchange_code<false>( new_exchange_code); } Forget the relevance of the is_arithmetic bit, I use my own needs_lock thingo. For a start: The compiler correctly identifies that ::type is not a member, but SFINAE does not seem to kick in if I'm reading it correctly. ____________________ c:\source\matt\trading_engine\controller\instrument.hpp(66) : error C2039: 'type' : is not a member of 'boost::enable_if_c<B,T>' with [ B=false, T=void ] c:\source\matt\trading_engine\controller\instrument.hpp(143) : see reference to class template instantiation 'te::instrument<S>' being compiled ____________________ template< bool > typename boost::disable_if_c< boost::is_arithmetic<std::string>::value , void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { exchange_code<false>( new_exchange_code); } Is fine... Flipping the conditions round by changing to is_arithmetic< int > flips the failures around. Same issue with the extra parameter approach: template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code, typename boost::enable_if_c< boost::is_arithmetic<int>::value, void >::type* dummy = 0 ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code, typename boost::disable_if_c< boost::is_arithmetic<int>::value , void >::type* dummy = 0 ) { exchange_code<false>( new_exchange_code); } Is SFINAE meant to work in this way with member templates with enable_if, vc7.1 and boost 1.31? Something simple is probably escaping me... Any thoughts? Regards, Matt Hurd. _______________ Matt Hurd +61.2.8226.5029 hurdm(a)sig.com Susquehanna _______________ 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.

2 1

Looking for more advanced type_traits-like functionality
by Agoston Bejo 08 Jun '04

08 Jun '04

Hi, I have took a look at some parts of the boost library, but I couldn't find what I want, and that is something like this: How can I determine if a type T has such and such member? It would look like something like this: has_member<T, paint>::result (true if T::paint() exists) has_member<T, m_size>::result (true if T::m_size exists) The closest to this I could find is boost::type_traits but that does not provide this functionality. Thx, Gus

4 6

boost::bind and boost::function fail at run-time in managed c++
by Russell Hind 08 Jun '04

08 Jun '04

Compiling the following code with /CLR on, results in an empty function exception at run-time. If you un-comment the #pragma unmanaged to get native compilation, it runs fine. Thanks Russell #include "stdafx.h" #using <mscorlib.dll> //#pragma unmanaged #include <boost/bind.hpp> #include <boost/function.hpp> class Test_c { public: void test(void) { } }; int main() { Test_c Test; boost::function<void (void)> f(boost::bind(&Test_c::test, &Test)); f(); return 0; }

1 2

remove_const, is_const with arrays
by Richard Crossley 08 Jun '04

08 Jun '04

I'm seeing, what appears to me anyhow, rather strange behaviour with is_const and remove_const etc when used with arrays. With VC71 and a recent cvs I see... is_same<remove_const<const int[1]>::type,int[1]>::value; // true is_const<const int[1]>::value; // false ?? is_same<remove_const<const int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_const<int[1][1]>::type,const int[1][1]>::value; // true is_const<const int[1][1]>::value; // false ?? is_volatile<volatile int[1]>::value; // false ?? is_same<remove_volatile<volatile int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_volatile<int[1][1]>::type,volatile int[1][1]>::value; // true Using Comeau 4.3.3; is_same<remove_const<const int[1]>::type,int[1]>::value; // true is_const<const int[1]>::value; // true is_same<remove_const<const int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_const<int[1][1]>::type,const int[1][1]>::value; // true is_const<const int[1][1]>::value; // true is_volatile<volatile int[1]>::value; // true is_same<remove_volatile<volatile int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_volatile<int[1][1]>::type,volatile int[1][1]>::value; // true Regards, Richard.

1 0

RE: [Boost-users] Looking for more advanced type_traits-likefunctionality
by Ben Hutchings 07 Jun '04

07 Jun '04

Agoston Bejo <gusz1(a)freemail.hu>: > Hi, > I have took a look at some parts of the boost library, but I couldn't > find what I want, and that is something like this: How can I determine > if a type T has such and such member? It would look like something > like this: > > has_member<T, paint>::result (true if T::paint() exists) > has_member<T, m_size>::result (true if T::m_size exists) > > The closest to this I could find is boost::type_traits but that does > not provide this functionality. Unfortunately that is impossible because templates can only manipulate constants, types and templates, not names. There is a technique that can be used to detect the definition of most operators, but it requires a separate template for each operator and it depends on being able to overload the operators through non-member functions. There may be a way to detect member functions but it cannot be done generically.

3 2

Re: Re: boost regex support for 64-bit
by Yaron Hirsch 07 Jun '04

07 Jun '04

> The errors that we got: > > 1. The Workshop 6 errors (SunOS): > > CC -c -O2 -I../../../ -o sunpro/libboost_regex/c_regex_traits.o > ../src/c_regex_traits.cpp > "../../..//boost/regex/v4/match_flags.hpp", line 91: Error: Cannot > assign int to boost::regex_constants::_match_flags. > "../../..//boost/regex/v4/match_flags.hpp", line 93: Error: Cannot > assign int to boost::regex_constants::_match_flags. > "../../..//boost/regex/v4/match_flags.hpp", line 95: Error: Cannot > assign int to boost::regex_constants::_match_flags. > 3 Error(s) detected. > > These are just a few. The rest of the errors occured for the same > reasons in various files. (If you want those too - > let me know). > > 2. The aCC errors are (HP-IX): > aCC -o generic/boost_regex/cpp_regex_traits.o -c -Aa -AA +O2 > -I../../../ -O ../src/cpp_regex_traits.cpp > Error 742: "../src/cpp_regex_traits.cpp", line 382 # Source type > const char *& and target type char * in a const_cast can only differ in > their qualifiers > pmd->sbuf.pubsetbuf(const_cast<char*>(first), > static_cast<std::streamsize>(last-first)); > > I mistakingly wrote dynamic_cast in the original post, but I meant > const_cast. Sorry for the confusion. > > Please notice that we had to add manually some flags to generic.mak > (which is the makefile we used to build it > on HP-IX). I'm aware of some example you gave in the html > documentation about compiling with aCC - but we still > had to change some flags. (I know these weren't formal settings and > just an example). > > Is there any chance that there will be a HP-IX-special makefile? It > will make life much easier. :-) > 3. I forgot to mension, that we managed to compile RegEX with SunOS C++ 5.5 both in 32 & 64 bits. There were no errors, BUT in 64 bits when we tried to run the rs/regress test - it failed (something which didn't happen in the 32-bits version). There was also a memory access violation, so even thought the compilation went just fine - apparently the library is not fully 64-bit compatible. What can we do to overcome this problem? Thanks alot, Yaron

2 3

boost::function and managed code
by Russell Hind 07 Jun '04

07 Jun '04

I'm looking for a way to get a boost::function to do a callback to a method of a managed C++ class in VS7.1. Has anyone managed to do this yet? Thanks Russell

2 2

VC60 Compilation error
by mhosni＠softhome.net 07 Jun '04

07 Jun '04

Hi all, while trying to compile the city_visitor.cpp example in the Graph lib with VC60 SP 3, I've got the following error -------------- --------------------Configuration: CityVisitor - Win32 Release-------------------- Compiling... CityVisitor.cpp C:\BOOST\INCLUDE\BOOST-1_31\boost/graph/depth_first_search.hpp(132) : error C2059: syntax error : 'static_cast' C:\BOOST\INCLUDE\BOOST-1_31\boost/graph/depth_first_search.hpp(228) : see reference to function template instantiation 'void __cdecl boost::detail::depth_first_visit_impl(const class boost::adjacency_list<struct boost::vecS,struct boost::vec S,struct boost::undirectedS,struct boost::no_property,struct boost::no_property,struct boost::no_property,struct boost::listS> &,unsigned int,class boost::dfs_visitor<struct std::pair<struct city_arrival,struct std::pair<struct neighbor_cities,struc t finish_city> > > &,class boost::iterator_property_map<enum boost::default_color_type *,struct boost::vec_adj_list_vertex_id_map<struct boost::no_property,unsigned int>,enum boost::default_color_type,enum boost::default_color_type &>,struct boost:: detail::nontruth2)' being compiled Error executing cl.exe. CityVisitor.exe - 1 error(s), 0 warning(s) --------------------------------------------- To be noted, the static_cast operator compiles normally in any other application. The archives of the mailing list contains a similar complain with iterator.hpp (dated Feb 2003 !!) but no solutions were posted in response. Anybody have any idea how to get through this problem Regards, M.Hosni

3 2

boost::bind problem
by Agoston Bejo 05 Jun '04

05 Jun '04

Hi, Please take a look at the code below. The point is that for_each_treenode calls for_each_treenode_child. It seems to me that bind(Print, ref(cout), _1)(&t); is not the same as Print(cout, &t); But if this is the case, how come that for_each_treenode_child(&t, bind(Print, ref(cout), _1)); compiles and works without problem? The compiler I use is VC 7.1. Thx, Gus ---------------------------------------------------------------------- // xBindTemplFuncPtr.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <iostream> #include <vector> #include <string> #include <boost/bind.hpp> #include <boost/ref.hpp> using namespace std; using namespace boost; template<typename TTree, typename TFunc> void for_each_treenode_child(TTree* t, TFunc f) { for_each(t->children.begin(), t->children.end(), f ); } template<typename TTree, typename TFunc> void for_each_treenode(TTree *t, TFunc f) { void (*thisFunc)(TTree*, TFunc) = for_each_treenode; // COMPILER BUG WORKAROUND - NOT RELEVANT NOW for_each_treenode_child( t, boost::bind(thisFunc, _1, f) ); f(t); } struct Tree { typedef vector<Tree*> Container; typedef Container::const_iterator const_iterator; typedef Container::iterator iterator; const_iterator begin() const { return children.begin(); } const_iterator end() const { return children.end(); } iterator begin() { return children.begin(); } iterator end() { return children.end(); } Tree(const string& sData):data(sData) {} vector<Tree*> children; string data; }; void Print(ostream& out, const Tree* pTree) { out << pTree->data << " "; } void PrintStd(const Tree* pTree) { Print(cout, pTree); } int _tmain(int argc, _TCHAR* argv[]) { Tree t("t"), t1("t1"), t2("t2"), t11("t11"), t12("t12"), t21("t21"); t.children.push_back(&t1); t1.children.push_back(&t11); t1.children.push_back(&t12); t.children.push_back(&t2); t2.children.push_back(&t21); Print(cout, &t); // WORKS bind(Print, ref(cout), _)(&t); // GENERATES ERROR (1) for_each_treenode(&t, bind(Print, ref(cout), _1)); // GENERATES ERROR (2) cout << endl; for_each_treenode(&t, PrintStd); // WORKS cout << endl; for_each_treenode_child(&t, bind(Print, ref(cout), _1)); // WORKS cout << endl; return 0; } ------------------------------------------------------------------------ Error for (1): error C2664: 'boost::_bi::bind_t<R,F,L>::result_type boost::_bi::bind_t<R,F,L>::operator ()<Tree*__w64 >(A1 & ) const' : cannot convert parameter 1 from 'Tree *__w64 ' to 'Tree *__w64 & ' with [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, A1=Tree *__w64 ] A reference that is not to 'const' cannot be bound to a non-lvalue Error for (2): c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind.hpp(246) : error C2664: 'void (TTree *,TFunc)' : cannot convert parameter 2 from 'boost::_bi::result_traits<R,F>::type' to 'boost::_bi::bind_t<R,F,L>' with [ TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *) ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2> ] Expressions of type void cannot be converted to other types c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind\bind_template.hpp(33) : see reference to function template instantiation 'R boost::_bi::list2<A1,A2>::operator ()<boost::_bi::bind_t<R,F,L>::result_type,void(__cdecl *)(TTree *,TFunc),boost::_bi::list1<Tree & >>(boost::_bi::type<T>,void,A &)' being compiled with [ R=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>:: result_type, A1=boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1, A2=boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>, T=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,bo ost::arg<1>>::B2>>::result_type, A=boost::_bi::list1<Tree *& > ] c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\algorithm(21) : see reference to function template instantiation 'boost::_bi::bind_t<R,F,L>::result_type boost::_bi::bind_t<R,F,L>::operator ()<std::allocator<_Ty>::value_type>(A1 & )' being compiled with [ R=void, F=void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), L=boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<v oid,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>, _Ty=Tree *, A1=std::allocator<Tree *>::value_type ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(18) : see reference to function template instantiation '_Fn1 std::for_each<std::vector<_Ty>::iterator,TFunc>(_InIt,_InIt,_Fn1)' being compiled with [ _Fn1=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>>, _Ty=Tree *, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<s td::ostream>,boost::arg<1>>::B2>>>::B2>>, _InIt=std::vector<Tree *>::iterator ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(29) : see reference to function template instantiation 'void for_each_treenode_child<TTree,boost::_bi::bind_t<R,F,L>>(TTree *,TFunc)' being compiled with [ TTree=Tree, R=void, F=void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), L=boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<v oid,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::refere nce_wrapper<std::ostream>,boost::arg<1>>::B2>>>::B2>> ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(68) : see reference to function template instantiation 'void for_each_treenode<Tree,boost::_bi::bind_t<R,F,L>>(TTree *,TFunc)' being compiled with [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind.hpp(246) : error C2664: 'void (TTree *,TFunc)' : cannot convert parameter 1 from 'boost::_bi::result_traits<R,F>::type' to 'Tree *' with [ TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *) ] Expressions of type void cannot be converted to other types

5 6

Boost.Threads && MFC?
by Philip, Tim 04 Jun '04

04 Jun '04

Has anyone ever used Boost.Threads in combination with MFC? MFC requires that threads using MFC functionality be created with AfxCreateThread(). What I'm wondering is if it is safe to create threads using AfxCreateThread() (instead of the Boost.Thread functionality) but then use the Boost.Threads mutexs and locking mechanisms to manage the thread activity. >From my brief perusal of the source it looks like it might work. But I was hoping I could find someone who had actually tried it and might have some experiences to share. :) Any information greatly appreciated! Thanks! Tim.

2 1

BGL: Pajek utility?
by Rui Carvalho 04 Jun '04

04 Jun '04

I'm looking for an utility to import/export graphs between the BGL and Pajek: http://vlado.fmf.uni-lj.si/pub/networks/pajek/ Does anyone know of such utility? Thanks, Rui ___________________________________ Dr. Rui Carvalho Research Fellow The Bartlett School of Graduate Studies 1-19 Torrington Place University College London Gower Street London WC1E 6BT United Kingdom

1 0

Thread usage question.
by Paul Gregory 04 Jun '04

04 Jun '04

Hello all, I am currently using Boost threads in a project I'm working on that involves a server/client type communications system. The project is a 3D renderer, the particular component is the communications between the renderer core, and any number of interested display clients, which are responsible for either displaying or storing the resulting image. Within the main program I have a listener thread that waits for requests from the display clients, and when it recieves one, launches another thread to handle the response. The responder thread can often just construct and send the response immediately. But if the request is for data that hasn't yet been rendered, it needs to wait for the data to be available. The responder is implemented as a class which has an operator() overload for the thread function. I would like for the responder thread to first query the system to see if the data is ready, and if not, block waiting for a signal from the system to indicate it is ready. So I need a way for the thread to 'register' it's interest in a particular data item with the main system, then wait for the signal. I presume there is a neat way of doing this using boost::mutexes and boost::condition's but I can't quite work out how, I freely admint I'm not very experienced when it comes to threaded programming. I've looked at the Boost bounded_buffer.cpp tutorial and it does something similar, but I can't work out how to apply the principles to my situation. Any help is greatly appreciated. Cheers Paul Gregory +---------------------------+---------------------------+ | email: pgregory(a)aqsis.com | Web: http://www.aqsis.com | | ICQ: 156088409 | AIM: aqsis1 | +---------------------------+---------------------------+ | GnuPG: http://aqsis.sourceforge.net/0x9176E46C.asc | +-------------------------------------------------------+

1 0

Some bad links on the web site
by Ross Boylan 04 Jun '04

04 Jun '04

The web site contains a bad link: http://lists.boost.org/mailman/listinfo.cgi/boost-announce directs you to http://lists.boost.org/MailArchives/boost-announce for the archives. That gives a 404 Not Found error. I think there was another bad link related to mailing lists, but I can't find it again. By the way, it would be good if the web site had where to send web-site related queries and bugs on the bottom of every page. As far as I could tell, this list is the place to go.

2 1

Date time Library: ptime and special_values
by Matthew_Schuckmann＠amat.com 04 Jun '04

04 Jun '04

The documentation for the date_time library states that a ptime can be constructed from a special value e.g. ptime(special_values sv) ptime t1(neg_infin); ptime t2(pos_infin); ptime t3(not_a_date_time); However when I try this with the Cygwin GNU compiler I get a no matching function for call error (see errors below) Am I missing something here or is the documentation wrong? Thanks Matt ../../logview.cpp:1843: error: no matching function for call to ` boost::posix_time::ptime::ptime(boost::date_time::special_values)' c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 32: error: candidates are: boost::posix_time::ptime::ptime(const boost::posix_time::ptime&) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 45: error: boost::posix_time::ptime::ptime(const boost::posix_time::int64_time_rep&) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 42: error: boost::posix_time::ptime::ptime(boost::gregorian::date) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 39: error: boost::posix_time::ptime::ptime(boost::gregorian::date, boost::posix_time::time_duration)

2 1