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boost::function Usage Question
by Albrecht Fritzsche 13 Aug '02

13 Aug '02

Consider the following code: class Publisher { typedef boost::function<void> Function; public: void SetChecker(const Function& Callback){ } }; class Manager { public: Manager(); private: void Check() {} }; Manager::Manager() { Publisher d; d.SetChecker(std::mem_fun(&Manager::Check)); } How can I get this to work? I always get an error when compiling the last line stating "..boost\function\function_template.hpp(127) : error C2660: '()' : Funktion akzeptiert keine 0 Parameter" Ah, the compiler is VisC++ 6. Thanks for any help Ali

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How to add user's rule to ALL?
by Lev Assinovsky 13 Aug '02

13 Aug '02

Hello folks! I defined my own rule to provide resource compilation. I put invocation of the rule in my Jambase file. But when I run bjam (not jam!) it skipped my rule. I believe that happens because my rule doesn't belong to 'all' list :"exe, lib ..." Should I try to define my rule in the style of EXE or there is more easy way to provide user''s rule invocation in BJAM? Any help will be appreciated! msvc-tools.jam: ------------------ cut here ------------------------ # resource rules for NT rule rescomp { DEPENDS $(<) : $(>) ; rescomp-impl $(<) : $(>) ; } actions rescomp-impl { rc /l "0x409" /d "_DEBUG" "$(>)" } ------------------------------------------------------- Jamfile: ---------------- cut here -------------------------- subproject ICIDM ; rescomp ICIDM.res : ICIDM.rc ; dll ICIDM : ICIDM.cpp ICIDMInterfaces.cpp SWMRGuard.cpp SysDep.cpp : <include>$(ADC_ROOT) <include>$(BOOST_ROOT) ; exe test : test.cpp <dll>ICIDM : <include>$(ADC_ROOT) <include>$(BOOST_ROOT) ; ------------------------------------------------------- ---- Lev Assinovsky Aelita Software Corporation O&S Core Division, Programmer ICQ# 165072909 [Non-text portions of this message have been removed]

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Problem with using special function
by sen_al2002 12 Aug '02

12 Aug '02

Hi, I am new to boost libraries. I just downloaded the whole BOOST_1_28_0 and I added the directory to compiler's list of #include<...> search paths but I still get error when I try to use the atanh() function. I am using Visual C++ v6.0 The error message reads d:\boost_1_28_0\atanh.hpp(77) : error C2989: 'atanh_helper1_t<T,0>' : template class has already been defined as a non-template class Could someone please help me out. Thanks Sen

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RE: [Boost-Users] Getting the hang of Boost::Bind
by Tom Matelich 12 Aug '02

12 Aug '02

> -----Original Message----- > From: Douglas Gregor [mailto:gregod@cs.rpi.edu] > Sent: Friday, August 09, 2002 3:32 PM > To: Boost-Users(a)yahoogroups.com > Subject: Re: [Boost-Users] Getting the hang of Boost::Bind > > > On Friday 09 August 2002 06:08 pm, Tom Matelich wrote: > > I have a vector of > > > > class Landmark > > { > > public: > > std::string const& getName() const; > > ... > > }; > > > > I want to do a find_if for a name that I have. > > > > something like > > std::find_if(begin, end, boost::bind(std::equal<std::string>(???, > > name_to_find))); > > > > What do I put for the ??? ? > > I presume that [begin, end) is an iterator sequence of > Landmark instances? > Then ??? = boost::bind(&Landmark::getName, _1), meaning that > the first > parameter to std::equal<std::string>::operator() is a call to > Landmark::getName where the object parameter (this) is the > first argument > (_1) to the bind function object. Thanks for the quick reply. That's what I thought. To make things more concrete... std::vector<Landmark> v; ... std::vector<Landmark>::const_iterator iter = std::find_if(v.begin(), v.end(), boost::bind(std::equal<std::string>, boost::bind(ZLandmark::Landmark::getName, _1), name_to_find)); Is what I think you're telling me. Perhaps I should mention now that I am using VC6. Compiling the above line I get many errors, here are the first three: inspdoc.cpp(453) : error C2780: 'class boost::_bi::bind_t<R,class boost::_mfi::dm<R,T>,class boost::_bi::list1<class boost::_bi::value<R> > > __cdecl boost::bind(R T::*,A1)' : expects 2 arguments - 3 provided c:\dev\opt\include\boost/bind.hpp(1362) : see declaration of 'bind' inspdoc.cpp(453) : error C2780: 'class boost::_bi::bind_t<R,struct boost::_mfi::cmf8<R,T,B1,B2,B3,B4,B5,B6,B7,B8>,class boost::_bi::list9<class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R> > > __cdecl boost::bind(R (__thiscall T::*)(B1,B2,B3,B4,B5,B6,B7, B8) const,A1,A2,A3,A4,A5,A6,A7,A8,A9)' : expects 10 arguments - 3 provided c:\dev\opt\include\boost/bind/bind_mf_cc.hpp(223) : see declaration of 'bind' inspdoc.cpp(453) : error C2780: 'class boost::_bi::bind_t<R,struct boost::_mfi::mf8<R,T,B1,B2,B3,B4,B5,B6,B7,B8>,class boost::_bi::list9<class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R>,class boost::_bi::value<R> > > __cdecl boost::bind(R (__thiscall T::*)(B1,B2,B3,B4,B5,B6,B7,B 8),A1,A2,A3,A4,A5,A6,A7,A8,A9)' : expects 10 arguments - 3 provided c:\dev\opt\include\boost/bind/bind_mf_cc.hpp(212) : see declaration of 'bind' Oh, and I guess that should be std::equal_to, right? Didn't work either though. Thanks, Tom PS Unfortunately, I have to run. I'll be looking at this again this weekend though. ----------------------------------------------------------------------- DISCLAIMER: Information contained in this message and/or attachment(s) may contain confidential information of Zetec, Inc. If you have received this transmission in error, please notify the sender by return email. -----------------------------------------------------------------------

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Changes I made to get boost::pool code to compile/execute under CW 8.1
by Ray S. Gallimore 12 Aug '02

12 Aug '02

Here is what I did to get boost::pool to compile/execute on CW 8.1: test_pool_alloc.cpp ============= 1) To execute w/o memory access violations, define BOOST_NO_PROPER_STL_DEALLOCATE sys_allocator.hpp =========== 1) To compile, change signature of allocate in both allocators from: static pointer allocate(const size_type n, const pointer = 0) to: static pointer allocate(const size_type n, const void* = 0) 2) To get time_pool_alloc.cpp to execute w/o memory access violations, change definition of new_delete_allocator from: { delete [] p; } to: { delete [] (char*)p; } Ray Gallimore

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Why does BGL use friend instead of member functions?
by Louis Lavery 11 Aug '02

11 Aug '02

Hi, It appears, to me, that the boost graph classes use friend functions and apposed to member functions. What are the reasons for this design decision (I like it) and why is the graph passed as the last argument? Thanks, Louis. PS. Great graph - great book.

2 1

Bad rules in bjam
by Lev Assinovsky 10 Aug '02

10 Aug '02

Hi folks! I found out that two major rules (from "allyourbase.jam") differ from classic Jam and can't work with full power (with gcc on solaris8-x86 at least). * Thus 'EXE' rule doesn't allow you linking with 3-rd party library (flag LINKFLAGS is ignored). * 'Main' rule skips compilation phase, though it's declared in the same allyourbase.jam: # Main image : source ; link executable from compiled sources Anyone experienced this? P.S. I had to built bjam since distribution doesn't have a pre-built version for solaris8-x86. ---- Lev Assinovsky Aelita Software Corporation O&S Core Division, Programmer ICQ# 165072909 [Non-text portions of this message have been removed]

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Getting the hang of Boost::Bind
by Tom Matelich 09 Aug '02

09 Aug '02

I have a vector of class Landmark { public: std::string const& getName() const; ... }; I want to do a find_if for a name that I have. something like std::find_if(begin, end, boost::bind(std::equal<std::string>(???, name_to_find))); What do I put for the ??? ? Thanks, Tom ----------------------------------------------------------------------- DISCLAIMER: Information contained in this message and/or attachment(s) may contain confidential information of Zetec, Inc. If you have received this transmission in error, please notify the sender by return email. -----------------------------------------------------------------------

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RE: [Boost-Users] Getting the hang of Boost::Bind
by Tom Matelich 09 Aug '02

09 Aug '02

> -----Original Message----- > From: Duane Murphy [mailto:duanemurphy@mac.com] > Sent: Friday, August 09, 2002 3:23 PM > To: Boost Users > Subject: Re: [Boost-Users] Getting the hang of Boost::Bind > > > --- At Fri, 9 Aug 2002 15:08:06 -0700, Tom Matelich wrote: > > >I have a vector of > > > >class Landmark > >{ > >public: > > std::string const& getName() const; > >... > >}; > > > >I want to do a find_if for a name that I have. > > > >something like > >std::find_if(begin, end, boost::bind(std::equal<std::string>(???, > >name_to_find))); > > > >What do I put for the ??? ? > > Nothing. Your done. :-) bind takes a pointer to a function > (among other > things) as the first parameter. It then calls that function with the > parameters you specify. You use _1, etc for parameters that > are input to > bind. In your case: > > std::find_if(begin, end, boost::bind(std::equal<std::string>, > name_to_find, _1))); > But I have to compare name_to_find to the result of _1.getName() don't I? ----------------------------------------------------------------------- DISCLAIMER: Information contained in this message and/or attachment(s) may contain confidential information of Zetec, Inc. If you have received this transmission in error, please notify the sender by return email. -----------------------------------------------------------------------

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Signals - no linking
by michael graves ii 09 Aug '02

09 Aug '02

hey, when trying to run a program using boost::signal i am getting a lot of unresolved errors. [output window] --------------------Configuration: my_dlls - Win32 Release-------------------- Linking... delegate_main.obj : error LNK2001: unresolved external symbol "public: __thiscall boost::signals::detail::signal_base::~signal_base(void)" (??1signal_base@detail@signals@boost@@QAE@XZ) delegate_main.obj : error LNK2001: unresolved external symbol "protected: __thiscall boost::signals::trackable::~trackable(void)" (??1trackable@signals@boost@@IAE@XZ) delegate_main.obj : error LNK2001: unresolved external symbol "public: void __thiscall boost::signals::connection::disconnect(void)const " (?disconnect@connection@signals@boost@@QBEXXZ) delegate_main.obj : error LNK2001: unresolved external symbol "protected: void __thiscall boost::signals::detail::slot_base::create_connection(void)" (?create_connection@slot_base@detail@signals@boost@@IAEXXZ) delegate_main.obj : error LNK2001: unresolved external symbol "public: __thiscall boost::signals::detail::signal_base_impl::signal_base_impl(class boost::function2<bool,class boost::any,class boost::any,struct boost::empty_function_policy,struct boo st::empty_function_mixin,int> const &)" (??0signal_base_impl@detail@signals@boost@@QAE@ABV?$function2@_NVany@boost@@ V12@Uempty_function_policy@2@Uempty_function_mixin@2@H@3@@Z) delegate_main.obj : error LNK2001: unresolved external symbol "public: class boost::signals::connection __thiscall boost::signals::detail::signal_base_impl::connect_slot(class boost::any const &,class boost::any const &,class std::vector<class boost ::signals::trackable const *,class std::allocator<class boost::signals::trackable const *> > const &)" (?connect_slot@signal_base_impl@detail@signals@boost@@QAE?AVconnection@34@AB Vany@4@0ABV?$vector@PBVtrackable@signals@boost@@V?$allocator@PBVtracka ble@signals@boost@@@std@@@std@@@Z) delegate_main.obj : error LNK2001: unresolved external symbol "public: __thiscall boost::signals::detail::call_notification::~call_notification(void)" (??1call_notification@detail@signals@boost@@QAE@XZ) delegate_main.obj : error LNK2001: unresolved external symbol "public: __thiscall boost::signals::detail::call_notification::call_notification(class boost::shared_ptr<class boost::signals::detail::signal_base_impl> const &)" (??0call_notification@de tail@signals@boost@@QAE@ABV?$shared_ptr@Vsignal_base_impl@detail@signals@boo st@@@3@@Z) delegate_main.obj : error LNK2001: unresolved external symbol "public: __thiscall boost::signals::detail::signal_base_impl::~signal_base_impl(void)" (??1signal_base_impl@detail@signals@boost@@QAE@XZ) Release/my_dlls.exe : fatal error LNK1120: 9 unresolved externals Error executing link.exe. my_dlls.exe - 10 error(s), 0 warning(s) [/output window] so in semi-readable for these are the unresolved symbols: signal_base::~signal_base(void) trackable::~trackable(void) void connection::disconnect(void)const void slot_base::create_connection(void) signal_base_impl::signal_base_impl(class boost::function2<bool,class boost::any,class boost::any,struct boost::empty_function_policy,struct boost::empty_function_mixin,int> const &) connection signal_base_impl::connect_slot(class boost::any const &,class boost::any const &,class std::vector<class boost::signals::trackable const *,class std::allocator<class boost::signals::trackable const *> >const &) call_notification::~call_notification(void) call_notification::call_notification(class boost::shared_ptr<class boost::signals::detail::signal_base_impl> const &) signal_base_impl::~signal_base_impl(void) i downloaded the signals library out of the CVS Repository. i see that some people have gotten signals to work so i guess i'm missing something=( i like this lib a lot (and it saves me from coding it=), but i would have went with a delegate/callback naming scheme instead of signal/slot. i guess that's what find and replace is for=). michael graves ii

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No time/date class in boost?
by Sean Shubin 09 Aug '02

09 Aug '02

I would have expected to find a time/date class in boost. Was it determined to be unnecessary, or is it simply that no one has gotten around to implementing one?

4 3

Regex issue on WIN32
by Rob Reece 09 Aug '02

09 Aug '02

I'm trying to get the regex lib (boost 1.28.0) built on win32 (MSVC v6, stlport 4.5.3). The standard build that is provided with regex appears to work fine and I get the full compliment of regex libraries (debug, static/dynamic, etc.). However, when I attempt to build the credit_card_example file, the link fails with unresolved external symbols. I then added the 13 regex source files to a msdev project along with the credit_card_example source file and linked everything statically (using BOOST_REGEX_STATIC_LINK or whatever it is). That worked fine. So this leads me to believe that something is going on with BOOST_REGEX_DECL macro. I put some #pragma message(...) statements into some headers and determined that the macro is being defined correctly. Is it possible that this macro is missing on some functions/classes or is it more likely a build option or macro issue? The first unresolved symbol I have is boost::re_detail::match_results_base<...>::m_free(...) As I was looking around for that symbol, I discovered in regex.hpp that match_results_base did not have BOOST_REGEX_DECL macro on the class definition. I added it and rebuilt and I ended up with more unresolved symbols. So obviously that isn't the direction to go. I have, however, not been able to find the actual definition of m_free yet (still looking). Thanks -Rob

2 1

Graph: Generic access to vertex/edge properties
by Tarjei Knapstad 09 Aug '02

09 Aug '02

Hi. I'm currently trying to implement a generic pattern matching (aka subgraph isomorphism) algorithm for use with the Boost Graph Library. My first-attempt function signature looks like this (comments included for further description of what I'm attempting) //! Seeks to find matches of the graph \a g2 in the graph \a g1. /*! This is called "graph pattern matching", or "subgraph homomorphism/isomorphism". The results are returned in a std::list of std::maps where the maps' key is the node_descriptor in \a g2 and the values are the corresponding node_descriptors in \a g1. The size of the returned list represents the number of matches. If \a properties is true it means that all vertex and edge properties must be equal in both structures for a match to be found. Otherwise, only the graph structure itself will be checked. \sa positioned_pattern_match */ template <class Graph> std::list< std::map<typename graph_traits<Graph>::vertex_descriptor, typename graph_traits<Graph>::vertex_descriptor> > pattern_match(const Graph& g1, const Graph& g2, bool properties = true); For the case where the 'properties' switch is false I have everything I need, but if 'properties' is true I'm a bit unsure on how to proceed. The problem, as I see it, is to do a generic consecutive access of all the properties of the current vertex/edge being checked and see if they're equal in both 'g1' and 'g2'. Could anyone provide me a solution/clue on how to solve this problem in a generic way so that the algorithm can be used for any graph? Regards, -- Tarjei Knapstad

3 2

VC7 build error without #define BOOST_DISABLE_WIN32
by Martin Schuerch 08 Aug '02

08 Aug '02

Hi I have an application with MFC / ATL and also some files compiled with the /clr option. Throuout the application boost is used a lot. All builds well as long as #define BOOST_DISABLE_WIN32 is set in the user.hpp file. Without this option a) the build hangs during registration after linking or b) link error due to differently defined custom attributes (in a file using /clr option) Did anybody had similar problems already? Regards Martin

1 0

iterator_adaptor and operator-> for input iterators
by Beman Dawes 07 Aug '02

07 Aug '02

I wrote an iterator to do recursive directory iteration. The heart of it is: template< typename Predicate > class recursive_directory_iterator : public boost::iterator_adaptor< boost::shared_ptr< detail::rdi_imp< Predicate > >, detail::rdi_policies, const boost::filesystem::path, const boost::filesystem::path &, const boost::filesystem::path *, std::input_iterator_tag, std::ptrdiff_t > { ... }; Works fine as long as you stay away from operator->. For example, fs::recursive_directory_iterator<pred_type> rdi( dir , dummy ); fs::recursive_directory_iterator<pred_type> rdi_end; for ( ; rdi != rdi_end; ++rdi ) { // std::cout << rdi->generic_path() << std::endl; std::cout << (*rdi).generic_path() << std::endl; } works as expected. But if you uncomment the commented line, the program fails in the call to operator->. What "fails" means depends on the execution environment; whatever is happening seems to confuse the debugger, stepping doesn't shed much light on the problem. Same symptoms with both VC++7 and Intel 6.0. I suppose I'm doing something stupid, but don't have a clue as to what. I notice in iterator_adaptor_test.cpp that operator-> is not actually exercised. Is it possible there is a bug in it for input iterators? I've not had similar problems with iterator_adaptor for bidirectional iterators. Any help appreciated, --Beman

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Newbie and his template for comments.
by Kamil Burzynski 07 Aug '02

07 Aug '02

Hello. I'm a C++ developer, who is learning STL recently, and loving it :) I've encountered Boost library, which seems to extending STL funcationality a lot :) I've also created a sampel template for usage in my company, and I would like to get comments about it: is this code ok, exception safe, somebody did it better things like that. In my projects I'm often using structures like map<T1, T2 *>, e.g. map<int, Point *> or map<string, Person*> or something like this. So, often I want to do something like that: map<int, Point *> my_map; map<int, Point *>::iterator it; /* .. */ for( it=my_map.begin();it!=my_map.end();++it ) { it->second->Reset(); //sets x,y to 0,0 } example may be stupid, but shows what I'm trying to explain. To improve it I've created a template (given below), so I ca use it like that: for_each( my_map.begin(), my_map.end(), map_fun( &Point::Reset ) ); Which i think is much better. My template is as follows (style is kept from GCC includes, so it may be not as readable as it could be :) template <class _Ret, class _Tp> class map_fun_t : public unary_function<_Tp*,_Ret> { public: explicit map_fun_t(_Ret (_Tp::*__pf)()) : _M_f(__pf) {} template< class _Mp> _Ret operator()(_Mp &__p) const { return ((__p.second)->*_M_f)(); } private: _Ret (_Tp::*_M_f)(); }; template <class _Ret, class _Tp> inline map_fun_t<_Ret,_Tp> map_fun(_Ret (_Tp::*__f)()) { return map_fun_t<_Ret,_Tp>(__f); } What do you think about it? Has it any flaws? Somebody done it already? Is it usable for anyone except me? :) Thanks in advance. -- Best regards from Kamil Burzynski Senior Design Engineer Advanced Digital Broadcast Poland, LTD. - - "Yes, I'm criminal. My crime is that of curiosity."

4 6

Regex++ link problem with VC6 when building with _UNICODE defined
by Edward Diener 07 Aug '02

07 Aug '02

If I build boost 1.28 regex with _UNICODE defined and then attempt to link the static mssd.lib version with a _UNICODE application using the library, I get: boost_regex_vc6_mssd.lib(w32_regex_traits.obj) : error LNK2005: _iswspace already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswalpha already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswupper already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswlower already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswdigit already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswxdigit already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswspace already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswpunct already defined in libcmtd.lib(_wctype.obj) boost_regex_vc6_mssd.lib(c_regex_traits.obj) : error LNK2005: _iswcntrl already defined in libcmtd.lib(_wctype.obj) Debug/TestRegularExpressionGUIStatic.exe : fatal error LNK1169: one or more multiply defined symbols found Error executing link.exe. This only occurs in the debug multi-threaded static library version. Has anyone else seen this or know why it might occur ? If I change the build options for this library from /Od /Gz to /O2, everything works fine and no linker errors occur.

2 1

[BGL] Common children for vertices in DAG
by Erik Arner 07 Aug '02

07 Aug '02

Is there a fast way, with or without preprocessing of the graph, for checking if two non-adjacent vertices in a DAG have one or more common children? Any pointers to components of the BGL that implement, or can be used to implement, this task would be much appreciated. Thanks, Erik

2 4

Tuple from cons list
by j1k1cki 07 Aug '02

07 Aug '02

Hi, Is there a simple way of obtaining a tuple type out of cons list? It also seems natural to build tuple type from two MPL iterators. Is such code available anywhere already? Best regards

1 0

BGL: Problem with parallel edges and filtered_graph
by Michael Kettner 06 Aug '02

06 Aug '02

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Jeremy, I think I discovered a problem concerning filtered_graphs and parallel edges: Assume I have a graph containing two edges E1 and E2 connecting node A and node B. Now I crate a boost::filtered_graph (myFilteredGraph) with a filter that returns true for only E1. When I now try to get E1 by calling edge = boost::edge( A, B, myFilteredGraph ).first; the result is undefined. Looking at the code (filtered_graph.hpp) I found out that the edge is return by: edge(typename filtered_graph<G, EP, VP>::vertex_descriptor u, typename filtered_graph<G, EP, VP>::vertex_descriptor v, const filtered_graph<G, EP, VP>& g) { typename G::edge_descriptor e; bool exists; tie(e, exists) = edge(u, v, g.m_g); return std::make_pair(e, exists && g.m_edge_pred(e)); } Here, the line tie(e, exists) = edge(u, v, g.m_g); returns _some_ edge, but not necessarily the _right_ one. The call edge(...) is not called for the filtered graph and g.m_edge_pred(e) is called _after_ getting the wrong edge (resulting in a return value FALSE). One solution would be to call boost::edge_range(A, B, myFilteredGraph) on my filtered_graph to get all visible edges, but this function is not provided. Any ideas how to solve my problem? Michael - -- http://www.ive.uni-hannover.de # kettner(a)ive.uni-hannover.de -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE9TqUAkCdGnb0kVFMRAlsLAJwKJJ2NSLRu2HUv/H4sAhr4W5WdkACdHXZ6 3kz8fBDvysWKc1vxd5rf/CE= =l+NV -----END PGP SIGNATURE-----

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BGL: dijkstra_shortest_paths and parallel edges
by Michael Kettner 06 Aug '02

06 Aug '02

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, my former posting leads me to another question: How does the dijkstra_shortest_paths behave if applied to a multigraph? And how does the dijkstra_shortest_paths behave if applied to a filtered_(multi)graph containing parallel edges, but with only _one_ of the parallel edges visible respectively? Michael - -- http://www.ive.uni-hannover.de # kettner(a)ive.uni-hannover.de -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE9TqprkCdGnb0kVFMRApGUAJ9nzr3Y4ijbrNnWENzxYIwcdLy8iQCfX2fx dl0M/IUt2bWFL0H9ovwajm4= =+FTJ -----END PGP SIGNATURE-----

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BGL example boost_web_graph.expected
by Arjun Bijanki 06 Aug '02

06 Aug '02

When I compile and run Boost_1_28_0/libs/graph/example/boost_web_graph.cpp my output differs from the expected output: 1c1 < The diameter of the boost web-site graph is 2 --- > The diameter of the boost web-site graph is 3 Is the expected file current? Thanks, Arjun Bijanki Microsoft VC++ [Non-text portions of this message have been removed]

2 1

Why stop building with error "Thread support is unavailable!"
by xuejm 06 Aug '02

06 Aug '02

Hi, I installed boost1.28.0 with microsoft visual c++ .NET and regex worked very well, but when I build a very simple example to test boost.thread, it stop building with error "Thread support is unavailable!". I found out that it's because that there's not a pre-define variable defined. Can I define the variable? How can I use boost.thread in my vc++ .net? TIA Phipps Xue

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Re: [Boost-Users] Re: Logical AND
by dan.ellis＠sophos.com 05 Aug '02

05 Aug '02

On 08/03/2002 05:04:26 PM news wrote: > > I need a match on "a AND is" when searching a sentence like "This is a > > test". >Regular expressions match sequences of characters. Your match says to match >a string when both of 2 different matching possibilities exist anywhere in >the string. To do this you must use 2 separate regular expression matches >separating them by the normal C++ "&&" operator. Maybe I'm misunderstanding what's wanted, but wouldn't is.*a do what he wants? Or if they need to be matched in either order: (is.*a)|(a.*is) It doesn't scale well, of course. -- Dan Ellis, Software Engineer, Sophos Anti-Virus Email: dan.ellis(a)sophos.com, DDI: 01235 540204 Real Business/CBI Growing Business Awards: Company of the Year Tel: 01235 559933, Web: http://www.sophos.com/

2 1

uBLAS Observation: terrible execution speed for prod(matrix,prod(matrix,prod(matrix,matrix)))
by Walter Bowen 05 Aug '02

05 Aug '02

Hi, I am new to uBLAS. I am looking to see if it will be useful for my application (I develop 6-Degrees-of-freedom flight simulations used to analyze avionics systems.) I have benchmarked a few lines of code with RogueWave's Math.h++ (testing for execution speed) and made the following observation. Observation 1) For matrix products of two small (~3-by-3) matrices ( i.e., prod(smallMat1, smallMat2) ) uBLAS executes MUCH FASTER than Math.h++. Observation 2) For matrix produces of two large matrices (100 by 100) uBLAS and Math.h++ give similar execuation speed. Obervation 3) (This is the kicker...) for strung-together matrix products like "Mat1 * Mat2 * Mat3 * Mat4 * Mat5", which I am implementing as "prod(Mat1, prod(Mat2, prod( Mat3, prod(Mat4,Mat5) ) ) ) Math.h++ is MUCH MUCH FASTER than uBLAS. -- by ~2 orders OF MAGNITUDE! I believe that this is a characteristic of the scalability of template expressions. My question is this: Is there a way I an instruct uBLAS not to use template expressions when for strung-together matrix products? Regards, Walt

5 4

Logical AND
by Mads M.P. 05 Aug '02

05 Aug '02

I've been looking for a parameter like "AND" when using regular expressions (from boost 1.28). I need a match on "a AND is" when searching a sentence like "This is a test". Is there a way to create such a search string by using regular expressions ? Regards Mads c(a)medit.dk

3 2

Boost 1.28 Regex and VC6 link problem
by Edward Diener 04 Aug '02

04 Aug '02

Using Boost 1.28 and regex I get linker errors regarding raw_storage. I believe someone has brought this up before but I didn't save the previous answer. error LNK2001: unresolved external symbol "public: class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> __fastcall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::allocator(void)const " error LNK2001: unresolved external symbol "public: class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> __fastcall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::allocator(void)const " error LNK2001: unresolved external symbol "public: __thiscall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >(class re_detail::detail::allocator_adapter<char,class boost::detail::simple_alloc> const &)" error LNK2001: unresolved external symbol "public: __thiscall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >(class re_detail::detail::allocator_adapter<char,class boost::detail::simple_alloc> const &)" error LNK2001: unresolved external symbol "public: void * __fastcall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::insert(unsigned int,unsigned int)" error LNK2001: unresolved external symbol "public: void __fastcall boost::re_detail::raw_storage<class boost::detail::allocator_adapter<char,class boost::detail::simple_alloc> >::resize(unsigned int)" It seems to be related to these lines in instances.hpp template class re_detail::raw_storage< BOOST_DEFAULT_ALLOCATOR BOOST_REGEX_CHAR_T) >; template class BOOST_REGEX_DECL re_detail::raw_storage<BOOST_DEFAULT_ALLOCATOR(BOOST_REGEX_CHAR_T) >; Are these lines in error ? Should one or both of them be removed ? My guess is that the line with BOOST_REGEX_DECL needs to be removed.

1 1

Problems with mpl::find and std library
by Tanton Gibbs 03 Aug '02

03 Aug '02

I had a problem with using mpl::find and the std::find at the same time. Basically, my compiler, Compaq C++ V6.5-026, notes an ambiguity in find.hpp between the find_if that it uses and the find_if in the STL. I changed the line that reads struct find : find_if< Sequence, same_as<T> > {}; to be struct find : mpl::find_if< Sequence, same_as<T> > {}; and it works fine. I'm not sure if this is a compiler bug or if we need to find other occurences like this one and fix them. Any help is appreciated. Tanton

2 2

boost.python - from_python for obj.__class__
by Nikolay Mladenov 02 Aug '02

02 Aug '02

Hi, I have exported some classes to python with boost.python, and now I am wondering: Does any body know how can I convert obj.__class__ (of an exported object from C++) to a class specific value( for example typeid(corespondong_cpp_class) )? Thanks in advance, Nikolay

1 0

bjam issue related to boost::python
by Srivatsan Raghavan 02 Aug '02

02 Aug '02

hi all , i created a c++ extension module using python which worked fine.. then i wanted to embed a call to PyRun_SimpleFile in another app, and the script i was calling is attempting to use my extension module but i was getting telling me that the interpreter wasn't initialized after much searching, research, and work with msvc's Dependency Walker i narrowed it down to the fact that boost_python_debug.dll is trying to link to the release version of python22.dll , whereas it should be linking to python22_d.dll (which unfortunately does not come with the python installer , that has to be compiled manually ) at any rate, how can the boost::python Jamfile be modified to try this check when it comes boost::python ? --vat ==.sig== Evil requires nothing more to win than that good men do nothing

1 0

[BGL] Vertex removal without iterator invalidation?
by Erik Arner 01 Aug '02

01 Aug '02

Yet another question from the BGL newbie... I understand that performing remove_vertex() on graphs with vertexList=vecS will result in invalidated itarors and descriptors for the graph. However, some toy examples i made suggest that if I remove a vertex in such a graph, the vertex descriptors and vertex iterators for vertices with *lower* ID than the removed vertex remain valid after removal, while those for higher ID vertices are invalidated. Is this a true feature of a graph with Vertexlist=vecS, or is my observation a mere coincidence? Is it safe to write code that exploits this "feature"? If it indeed is a feature, I can construct a sorted list of vertices to remove, and remove the vertices in descending order in an easy fashion. If it is not a feature, any suggestions on how to perform this task i.e. removing a list of vertices while keeping the VertexList type vecS? Thanks, Erik

2 2

collection container
by Bohdan 01 Aug '02

01 Aug '02

Has boost any plans on creating container, that holds data by pointer, not by value? Rationale: It is impossible to use normally vector<...> for types that do not have copy constructor. Interface of vector< shared_ptr<...> > doesn't seems to be very convenient( for example with std::algorithms ). And most of all it is not good idea to show vector< shared_ptr<...> > interface to user of my lib, that wants to have container::iterator with normal behavior. AFAIK majority of existing libraries have/need such container ? As to me it is strange that neither stl nor boost have such class. I'm missing 'something' and there are important reasons for not doing this ?

2 5

Creating groups of regular expressions
by cyndi_r2002 01 Aug '02

01 Aug '02

Hi, I have started using Regex++ and like it a lot but is there a way to use grouping constructs using Regex++ / any alternative that would provide the same functionality? Thanks, Cyndi

2 1

Newbie link problem
by Lev Assinovsky 01 Aug '02

01 Aug '02

Hi all! I would like to do a very simple thing: link my main tst.cpp with the third party library $(MYDIR)/libfoo.a. The final command line should be: g++ -o tst tst.cpp -L$(MYDIR) -lfoo Currently I have in my Jamfile: exe tst : tst.cpp : <include>$(ADC_ROOT) <include>$(BOOST_ROOT) <include>"$(HOME)/inc" ; What must be added to provide linking with libfoo.a? (adding of variable LINKLIBS=$(MYDIR)/libfoo.a DOESN'T WORK) Thanks in advance! ---- Lev Assinovsky Aelita Software Corporation O&S Core Division, Programmer ICQ# 165072909 [Non-text portions of this message have been removed]

1 0

boost working with CGAL ??
by Matthias Kronenberger 31 Jul '02

31 Jul '02

I want to use CGAL from http://www.cgal.org together with the boost library. I'm using MSVC 6.5 There seem to be some problems related to namespace issues. I'm getting the following kind of errors: d:\matthias\programmieren\cgal\include\cgal\number_utils.h(236): error C2955: 'is_integral': Fuer die Verwendung einer Vorlagenklasse ist eine Vorlagen-Argumentliste erforderlich d:\matthias\programmieren\boost\boost\type_traits\arithmetic_traits.hpp(38): Siehe Deklaration von 'is_integral'

1 0

Cannot put .o File with Graph Code into .a File
by Adalbert Perbandt 30 Jul '02

30 Jul '02

Hi there, while trying to setup the BGL for use in my environment I'm facing a strange behavior when I try to put a C++ object file which contains instanciations of BGL templates into an object library. My environment: - Sun SPARC machine with Solaris 2.7 (SunOS 5.7) - gcc 2.95.2 The problem shows up when I try to put an .o file into a library file. I can reproduce the error with the file adjacency_list.cpp from the BGL's examples directory: $ pwd /home/perbandt/boost_1_28_0/libs/graph/example $ g++ --version 2.95.2 $ g++ -g -I../../../../boost_1_28_0 -c adjacency_list.cpp $ ls -l adjacency_list.o -rw-r--r-- 1 perbandt relman 3367052 Jul 19 18:40 adjacency_list.o $ which ar /usr/ccs/bin/ar $ ar rv libtest.a adjacency_list.o a - adjacency_list.o Bus error When I try a .a file with already one or more .o files in it I get a segmentation fault. With another file that contains instantiations of BGL templates the problem does appear only when it was compiled with the -g option given. Is this a known problem? Seems to me as if ar would have trouble handling the very long symbol names in the .o file. Or is something wrong with my environment? Thanks, Adalbert Perbandt.

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RE: [Boost-Users] absolute beginner, trying to compile
by James Zappia 30 Jul '02

30 Jul '02

It should be /usr/include/boost Then you can do: #include <boost/whatever.h> /usr/include is the base directory. So how you have it now it would be: #include <boost_1_28_0/boost/whatever.h> And you definitely don't want to do that. Regards, James -----Original Message----- From: thomas strack [mailto:yg-boost-users@gmane.org] Sent: Tuesday, July 30, 2002 10:17 AM To: boost-users(a)yahoogroups.com Subject: [Boost-Users] absolute beginner, trying to compile hi there, unfortunately im not very experienced in c/c++. but i want to try out some functions from the boost libs. so i downloaded and extracted the files (1_28_0) to /usr/include/boost_1_28_0. i think i should be able to use most of the functions now(i hope i didnt misunderstand the doc). i want to use dir_it lib, but i cant compile the testfile coming along with boost. it includes <boost/directory.h> and g++ cant find this file. i dont know exactly how to use the -I and -l options. it would be great if someone could help me out. thx,tommi Info: <http://www.boost.org> Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

1 0

absolute beginner, trying to compile
by thomas strack 30 Jul '02

30 Jul '02

hi there, unfortunately im not very experienced in c/c++. but i want to try out some functions from the boost libs. so i downloaded and extracted the files (1_28_0) to /usr/include/boost_1_28_0. i think i should be able to use most of the functions now(i hope i didnt misunderstand the doc). i want to use dir_it lib, but i cant compile the testfile coming along with boost. it includes <boost/directory.h> and g++ cant find this file. i dont know exactly how to use the -I and -l options. it would be great if someone could help me out. thx,tommi

1 0

Boost.Lambda - Invoking functors stored in a vector
by Thomas Wenisch 30 Jul '02

30 Jul '02

Hi all, I am storing a set of functors to be invoked in a vector, like this: std::vector< boost::function<void> > functors; At a later time, I would like to invoke each of the functors in the vector. I am trying to do this using Boost.Lambda, to start learning about the Lambda library, but I can't figure out what to write. if I write: std::for_each(functors.begin(), functors.end(), _1); None of the functions are invoked. if I try: for_each(funtors.begin(), functors.end(), _1()); I get compile errors. I suspect this is because the lamda expression is being executed immediately instead of getting passed in to for_each. Everything works fine when I use a separate Invoker function in the usual fashion, like this: void Invoker( boost::function<void> functor) { functor(); } std::for_each(funtors.begin(), functors.end(), Invoker); How can I get the lambda library to invoke each function in the vector? More generally, if the functions were function<void, T>, how could I bind the T parameter in the lambda expression? Thanks for any help, Tom Wenisch Computer Architecture Lab Carnegie Mellon University

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Johnsons BGL implementation for undirected graphs correct?
by Jan de Ruiter 29 Jul '02

29 Jul '02

When I use the BGL johnsons_all_pairs_shortest_paths example (source below)on an undirected graph, some results are quite wrong. For example, the output shows that the distance between node 1 and 6 equals 36. The SP however (1-4-5-8-9-6) = 4+4+4+12+2 = 26. Is there something wrong with me or is the BGL implementation incorrect? Any ideas? Jan de Ruiter //Output 0 1 2 3 4 5 6 7 8 9 0 0 99 111 123 103 107 135 105 111 123 1 -99 0 12 24 4 8 36 6 12 24 2 -111 -12 0 12 -8 -4 24 -6 0 12 3 -123 -24 -12 0 -20 -16 12 -18 -12 0 4 -103 -4 8 20 0 4 32 2 8 20 5 -107 -8 4 16 -4 0 28 -2 4 16 6 -135 -36 -24 -12 -32 -28 0 -30 -24 -12 7 -105 -6 6 18 -2 2 30 0 6 18 8 -111 -12 0 12 -8 -4 24 -6 0 12 9 -123 -24 -12 0 -20 -16 12 -18 -12 0 ------------------------------------------------------------------------- //Source #include <boost/config.hpp> #include <fstream> #include <iostream> #include <vector> #include <iomanip> #include <boost/property_map.hpp> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/graphviz.hpp> #include <boost/graph/johnson_all_pairs_shortest.hpp> int main() { using namespace boost; typedef adjacency_list<vecS, vecS, undirectedS, no_property, property< edge_weight_t, int, property< edge_weight2_t, int > > > Graph; const int V = 10; typedef std::pair < int, int >Edge; Edge edge_array[] = { Edge(0,1), Edge(1,2), Edge(2,3), Edge(1,4), Edge(2,5), Edge(3,6), Edge(4,5), Edge(5,6), Edge(4,7), Edge(5,8), Edge(6,9), Edge(7,8), Edge(8,9) }; const std::size_t E = sizeof(edge_array) / sizeof(Edge); Graph g(edge_array, edge_array + E, V); property_map < Graph, edge_weight_t >::type w = get(edge_weight, g); int weights[] = { 99, 12, 12, 4, 99, 12, 4, 99, 2, 4, 2, 99, 12 }; int *wp = weights; graph_traits < Graph >::edge_iterator e, e_end; for (boost::tie(e, e_end) = edges(g); e != e_end; ++e) w[*e] = *wp++; std::vector < int >d(V, std::numeric_limits < int >::max()); int D[V][V]; johnson_all_pairs_shortest_paths(g, D, distance_map(&d[0])); std::cout << std::setw(5) <<" "; for (int k = 0; k < 10; ++k) std::cout << std::setw(5) << k ; std::cout << std::endl; for (int i = 0; i < 10; ++i) { std::cout <<std::setw(5) << i ; for (int j = 0; j < 10; ++j) { std::cout << std::setw(5) << D[i][j] ; } std::cout << std::endl; } return 0; }

4 4

[BGL] Detection of cycles in graphs
by Erik Arner 29 Jul '02

29 Jul '02

This is a repost - I sent it last friday but it hasn't shown up, so I'll try again: Is there an algorithm implemented in BGL that detects whether a directed graph contains cycles or not? If not, what would be the best way to implement such an algorithm? Thanks, Erik

2 1

Pass through buffer
by Tom Howard 29 Jul '02

29 Jul '02

Hi, I'm wondering if someone can help me with the pass through buffer (basic_passthrubuf) that is part of more_io. >From what I can understand the pass though buffer passes 1 character at a time to (and from) the underlying stream buffer and I'm wondering what happens with flushes. In the code I'm working on (gzostreambuf which writes to an ostream) I need to know is overflow() is being called because there is no more room in the buffer I'm using or because of an explicit flush. In the later case I need to also flush the compression (Z_SYNC_FLUSH), but doing so all the time will degrade the compression performance plus increase the number of flushes to the underlying stream. This is particularly bad as the underlying stream in my case is a socket stream an the increased flushes breaks up the data into many small packets. Because of the software at the other end of the socket, data must be sent as one message unless it's over 8096 bytes. So basically I only want to flush the underlying stream if the gzostreambuf has been flushed (either by endl or flush). is this possible? My current workaround is to make sure the buffersize of my gzostreambuf is greater than or equal to the buffersize of the underlying stream, but I was hoping there was a neater solution and thats why I was looking at the pass through buffer. >From what I unbderstand, If I use the pass through buffer as part of my gzostreambuf, then flushing will not be passed to the underling streambuf at all. This means that data sent to the stream may be compressed, but result in no output for quite some time later and this sort of latency would be unacceptable in the software I'm working on (client-server multi-agent simulation). Cheers, Tom Howard

1 0

regex_search matches correctly but memory holder contains wrong value
by Anibal Jodorcovsky 29 Jul '02

29 Jul '02

Hi all, I have a small problem when trying out a regex that works ok with both jakarta (java code) and Perl. However, in boost::regex I get an extra space that's very weird. This is the code: #include <iostream> #include <string> #include <boost/regex.hpp> main() { static const boost::regex infileRedirection( "\\[(.+?)\\s*=\\s*(.+?)\\]" ); const string input = "[IN_FILE_REDIRECTION = STARTS_3]"; boost::cmatch what; if ( boost::regex_search( input, what, infileRedirection, boost::regbase::perl ) ) { cerr << "Matched! == input is (" << input << ")" << endl; string mySection; mySection.assign( what[1].first, what[1].second ); string newSectionName; newSectionName.assign( what[2].first, what[2].second ); cerr << "mySection is: --" << mySection << "--" << endl; cerr << "newSection is: --" << newSectionName << "--" << endl; } else { cerr << "Didn't match" << endl; } return 0; } And this is the output: [anibal@anibal ControlFile]$ ./a.out Matched! == input is ([IN_FILE_REDIRECTION = STARTS_3]) mySection is: --IN_FILE_REDIRECTION-- newSection is: -- STARTS_3-- Please note the extra space in the newSection. That should be STARTS_3 and not " STARTS_3". Why is it taking that space if the space itself is not in the () expression? Any help greatly appreciated, -Anibal

2 1

Compilation problem
by Sergey Belovolov 29 Jul '02

29 Jul '02

gcc version 2.95.3 20010315 (release). It came with OS (SunOS 5.8 x86). After when I compiled & installed bjam I came into boost root dir and give (as it suggessted in docs): bjam "-sTOOLS=gcc". It builds 3 library: libboost_regex.a, libboost_regex.so, libboost_thread.a (while bjam builds library libboost_thread.a it throws messages: " g++: unrecognized option '-pthreads' "). Then I copy them into some dir that included in LD_LIBRARY_PATH environment varyable and copy dir boost to /usr/include. Then I create file with contents: #include <boost/thread/mutex.hpp> main() { return 0; } and compile it with: g++ test.cpp. Results: In file included from /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/uti lity:31, from /usr/include/boost/config/select_stdlib_config.hpp:18, from /usr/include/boost/config.hpp:40, from /usr/include/boost/thread/mutex.hpp:15, from test.cpp:1: /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h: In function `bool rel_ops::operator !=(const _Tp &, const _Tp &)': /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h:37: template with C linkage /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h: In function `bool rel_ops::operator >(const _Tp &, const _Tp &)': /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h:42: template with C linkage /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h: In function `bool rel_ops::operator <=(const _Tp &, const _Tp &)': /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h:47: template with C linkage /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h: In function `bool rel_ops::operator >=(const _Tp &, const _Tp &)': /opt/sfw/lib/gcc-lib/i386-pc-solaris2.8/2.95.3/../../../../include/g++-3/stl _relops.h:52: template with C linkage and so on and so on... What's wrong? Why it says that STL templates use C linkage? Thanks for help in advance. Sergey Belovolov. b_sv(a)mail.ru SBelovolov(a)algorithm.aelita.com

1 0

Installation problems
by fauzia_sharmeen 28 Jul '02

28 Jul '02

Hi, After downloading and unzipping the Regex library with the -d option, I ran nmake -fvc6.mak on the command prompt.However, I am getting an error message saying "Variable MSVCDIR not set". I checked the VcVars32.bat file to verify that the variable MSVCDIR has been set properly. Any ideas/suggestions about what I am doing wrong would be most appreciated. Thanks, Fauzia

4 3

Iterator problem with adjacent_vertices
by EJ van Eijk 28 Jul '02

28 Jul '02

Hello, I'm currently implementing some algorithms for drawing graphs, using boost::graph. PropertyMaps e.a. are working like a charm, but for my algorithm I need to find the adjacent vertices. Now I've become stuck on the following: typedef boost::adjacency_list < boost::mapS, boost::vecS, boost::undirectedS, VertexProperty, EdgeProperty> Graph; typedef boost::graph_traits<Graph>::vertex_descriptor Vertex; class functor { ... void operator()(Vertex& v) { ... }; }; for_each(adjacent_vertices(u,g).first, adjacent_vertices(u,g).second, functor<Graph>(g)); complains about foo.cc:30: initialization of non-const reference type `Vertex &' foo.cc:30: from rvalue of type `unsigned int' But, when using vertices(g) instead of adjacent_vertices(v,g), the code compiles, and applies functor to each vertex. What am I missing? The documentation is quite thorough, but I'm lost at the moment... EJ

1 0

Re: [Boost-Users] XML
by dick.bridges＠tais.com 26 Jul '02

26 Jul '02

What you say is true. In fact, it's *STILL* true. In the meantime, Xerces has released version 1.7.0 and, most recently, version 2.0. I've been following the Xalan mail lists and comments from some of the developers suggest that co-ordination between the two groups could be better. This "thread" probably belongs on xalan-c-users(a)xml.apache.org. Mail me direct to continue. Albrecht Fritzsche <albrecht.fritzsche@tisc To: Boost-Users(a)yahoogroups.com ali-dsl.de> cc: Subject: Re: [Boost-Users] XML 07/26/2002 11:33 AM Please respond to Boost-Users dick.bridges(a)tais.com wrote: > Unfortunately, the Xerces and Xalan projects don't appear to > be all that well co-ordinated. Makes it difficult to stay both > current and compatible. Huh - why do you think that? Simply reading the FAQ gives me "The Xalan-C++ release notes includes information about the Xerces-C++ release with which the Xalan-C++ release has been coordinated and tested." and even the Readme says "Xalan-C++ version 1.3 has been tested with Xerces-C++ version 1.6.0. Each Xalan-C++ version 1.3 download includes the Xerces-C++ distribution for the specified platform." Curious Ali Info: <http://www.boost.org> Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

1 0

RE: [Boost-Users] XML
by dick.bridges＠tais.com 26 Jul '02

26 Jul '02

Xerces is ok for xml+namespaces but if you want to use additional facilities (e.g., XPath, XSLT, etc.) you'll have to go to other packages like Xalan. Unfortunately, the Xerces and Xalan projects don't appear to be all that well co-ordinated. Makes it difficult to stay both current and compatible. It sure would be nice to have a "boost-level" C++ library for xml but I'm not sure we could sell the idea that it should be "part of" C++. Hope I'm wrong. schalk_cronje@na i.com To: Boost-Users(a)yahoogroups.com cc: 07/26/2002 10:14 Subject: RE: [Boost-Users] XML AM Please respond to Boost-Users > I'm writing an XML based project right now. I haven't been > able to find > any good, open source XML parser to incorporate into my > application, so I What's wrong with Xerces? Info: <http://www.boost.org> Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

3 2

RE: [Boost-Users] Re: [boost] Iterator Adaptor Poll
by Mark Storer 26 Jul '02

26 Jul '02

May i recommend providing both the "hello world" grade example, and something more real-world... like that path token iterator you mentioned? --Mark Storer Software Engineer Cardiff Software #include <disclaimer> typedef std::disclaimer<Cardiff> Discard;

1 0

Re: [boost] Iterator Adaptor Poll
by David Abrahams 26 Jul '02

26 Jul '02

From: "Toon Knapen" <toon.knapen(a)si-lab.org> > > Sure, I'm all for toys, as in "this doesn't really do everything I'd want > > from a real example, but it shows me how the system works". The problem I > > have with ia_experiment.cpp is that my first reaction was "why would anyone > > want an "iterator" which does *that*?" The fact that it iterates over only > > two elements and stores its value internally is pretty weird. I think most > > people who have only seen the standard iterators would have a hard time > > imagining that this is also an iterator. Though technically, it is an > > iterator, it's so different in nature from most iterators that it seems > > like it would be completely foreign. > > > > What about a singly-linked-list iterator example? Wouldn't that show > > everything you're illustrating, but more transparently? > > Why not some kind of rotation iterator. The advantage of this example is that > there's a std::rotate in the STL which modifies the container whereas the > rotation_iterator_adaptor can give you the same result but withouth modifying > the containers. AFAICT this is a strong argument in favour of the IA. That's neat, but we already have the permutation adaptor, and I don't think it's really a simple enough example. Beman's example just makes a simple iterator, not an adaptor, and I think that's an important feature for a "hello, world"-type introduction. -Dave ----------------------------------------------------------- David Abrahams * Boost Consulting dave(a)boost-consulting.com * http://www.boost-consulting.com

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