October 2002 - Boost-users - lists.boost.org

boost::shared_ptr and stl algorithms
by Bill Eidson 14 Apr '05

14 Apr '05

std::vector< boost::shared_ptr<T> > TVec; I want to write a function object to run std::for_each. to do somework against members of T and accumulate results in functor. My attempts have failed in VC7 with memory errors in my operator() method. struct fo { bool operator()( boost::shared_ptr<T>& t ) { return true; } }; Thanks in advance bille

5 9

BGL and reversing / moving edges
by joshrose 17 Dec '03

17 Dec '03

G'day, I was hoping someone might be able to tell me if they've run into any situations using BGL where they needed to move (or reverse (i.e. flip the source and target)) an edge within a graph implemented as an adjacency_list. I'm working on an implementation of an algorithm for max. weight bipartite matching ("the assignment problem"), and one of the assumptions in the algorithm is that non-matched edges are directed from one subgraph, A, to the other subgraph, B, and matched edges are directed the other way. Over the course of growing the matching, a simple way to add and remove edges from the candidate set is just to reverse the edge, thus the need for some way to reverse the edge within BGL. I don't think I can just remove and then re-add the edge in the other direction, primarily because doing so will (I believe) invalidate any edge_descriptors referring to that edge. In particular, there are property maps keeping track of the weight of edges, the predecessors of certain nodes, etc. that use edge descriptors as keys. I've spent a fair bit of time reading the documentation and looking through the implementation of adjacency_lists (incl. edge_list_impl), and I'm not really sure of a way to either move an edge directly within a graph, or even to create a new edge from another s.t. they have the same edge_descriptor (in general a bad thing, probably). Anyone have any thoughts on this? Thanks, -Josh

4 10

bjam and windows command line problem.
by Fernando Cacciola 07 May '03

07 May '03

Hi, I'm having a hard time trying to use bjam to build boost 1.29.0. I have Win98 in Spanish, and I use Borland C++ Builder 5.0 (its bcc32.exe corresponds to is BCC5.5.1) I have boost 1.29.0 installed at: "C:\Libraries\boost\Repository\boost" I've downloaded bjam for Microsoft Windows: >bjam -v Boost.Jam Version 3.1.0. OS=NT. Copyright 1993-2002 Christopher Seiwald and Perforce Software, Inc. Copyright 2001 David Turner. Copyright 2001-2002 David Abrahams. I've temporarily modified the root 'jamfile' so that it builds only the Test library. and I've done: subst d: "c:\archivos de programa\borland\cbuilder5" set BCCROOT=d: (you'll see why in a moment) If I try: c:\>cd C:\Libraries\boost\Repository\boost" C:\Libraries\boost\Repository\boost> bjam -sTOOLS=borland I receive messages of the form: borland-C++-action libs\test\build\bin\libpem.lib\borland\debug\runtime-link-static\threading-s ingle\execution_monitor.obj "d:\bin\bcc32" -j5 -q -c -P -w -Ve -Vx -a8 -v -Od -vi- -tWC -WM- -w-8001 -I"libs\test\build" -I"C:\Libraries\boost\Repository\boost" -I"d:\includ e" -o"libs\test\build\bin\libpem.lib\borland\debug\runtime-link-static\thre ading-single\execution_moni Error E2266: No file names given tor.obj" "libs\test\build\../src\execution_monitor.cpp" C:\WINDOWS\TEMP\JAMTMP00.BAT [2] Unknown command "TOR.OBJ" "LIBS\TEST\BUILD\.." "d:\bin\bcc32" -j5 -q -c -P -w -Ve -Vx -a8 -v -Od -vi- -tWC -WM- -w-8001 -I"libs\test\build" -I"C:\Libraries\boost\Repository\boost" -I"d:\includ e" -o"libs\test\build\bin\libpem.lib\borland\debug\runtime-link-static\thre ading-single\execution_monitor.obj" "libs\test\build\../src\execution_monitor.cpp" ...failed borland-C++-action libs\test\build\bin\libpem.lib\borland\debug\runtime-link-static\threading-s ingle\execution_monitor.obj... If I'm interpreting this output correctly, the problem is that the command line feed to bcc32 exceeds 256 characters. What can be done about this? Is there a way for 'borland-tools.jam' to put the bcc32 parameters in a tmp response file and use: bcc32.exe @tmprsp.rsp? Any help will be appreciated. TIA, -- Fernando Cacciola

4 22

VC7 says 'fatal C1067' compiling multi_array?
by Clift Norris 01 Mar '03

01 Mar '03

Greetings: I'm using VC7 and boost_1_29_0 to compile this code that is using multi_array.hpp. typedef boost::multi_array<double, 4> theta4_t; typedef theta4_t::index index; theta4_t Theta_Trun( boost::extents[10000][2][10][256] ); I'm receiving this error: "fatal error C1067: compiler limit: debug information module size exceeded" Of course, the code compiles fine using the "Release" configuration, but I need the "Debug" one also. Is there a workaround for this, other than the 'make your variables shorter' suggested in the VC7 documentation? Thanks, -Clift

2 1

bug report: boost::tokenizer with VC6
by Navi Singh 09 Feb '03

09 Feb '03

The boost release 1.28.0 of the tokenizer library has the following problem: There are 5 examples, namely, simple_example_1.cpp thru simple_example_5.cpp If I change the main() in each of the 5 to to main1() thru main5() and return 0; the vc60 compiler generates an internal compiler error when parsing the file boost\iterator_adapters.hpp on line 869, where it is parsing the following lines: reference operator*() const { return policies().dereference(*this); }

3 2

Q: Graphs. Sorting edges. Possible? How to?
by stas_fomin 07 Nov '02

07 Nov '02

Hello. I a newbie in BGL and I rewrite my LEDA code now... I have to sort (order) edges according to some functor. For example (simplified): typedef adjacency_list<vecS, vecS, bidirectionalS> MyGraph; typedef graph_traits < MyGraph >::edge_descriptor MyGraphEdge; typedef graph_traits < MyGraph >::edge_iterator MyEdgeIter; class MyCompareEdges{ public: bool operator()(MyGraphEdge e1, MyGraphEdge e2) const { return true; } }; .... { MyGraph Gr(10); MyEdgeIter ei_beg, ei_end; MyCompareEdges comp; tie(ei_beg, ei_end) = edges(Gr); std::sort(ei_beg, ei_end, comp); //Error C2676 } And I have error C2676 (below the message...). Questions: 1. Is it possible to sort edges in the graph? 2. How to... Thanks all in advance... Stas Fomin. P.S. vecS, setS, listS for edge container... - C2676. ------------------------------ d:\projects\lib\cpp_libs\libboost\boost\iterator_adaptors.hpp(264) : error C2676: binary '+=' : 'class std::list<struct boost::list_edge<unsigned int,struct boost::no_property>,class std::allocator<struct boost::list_edge<unsigned int,struct boost:: no_property> > >::iterator' does not define this operator or a conversion to a type acceptable to the predefined operator d:\projects\lib\cpp_libs\libboost\boost\iterator_adaptors.hpp (911) : see reference to function template instantiation 'void __thiscall boost::default_iterator_policies::advance(struct boost::iterator_adaptor<class std::list<struct boost::lis t_edge<unsigned int,struct boost::no_property>,class std::allocator<struct boost::list_edge<unsigned int,struct boost::no_property> > >::iterator,struct boost::detail::undirected_edge_iter_policies,class boost::detail::edge_desc_impl<struct boost::b idirectional_tag,unsigned int>,class boost::detail::edge_desc_impl<struct boost::bidirectional_tag,unsigned int>,class boost::detail::edge_desc_impl<struct boost::bidirectional_tag,unsigned int> *,struct boost::multi_pass_input_iterator_tag,int> &,i nt)' being compiled Error executing cl.exe.

4 7

Q: Problems building boost.python under cygwin
by "Schnörr, Claudius Dr." 06 Nov '02

06 Nov '02

Hello, I run into problems building boost under cygwin. It seems to be merely a matter of a wrong configuration or wrong scripts. After running 'bjam -sTOOLS=gcc -n > build.com' in boost/libs/python/build in order to get hands on the statements being executed by bjam, there had to be made a lot of textual replacements to get the statements in build.com run: Just to mention some: - replace '-isystem ' by '-I' - remove '-I""' - change shared library-names from *.so to *.dll - insert '-L <path_to_libpython2.2.dll> -lpython2.2' where shared libs are created In boost/libs/python/test, going the same way, there have in addition this changes to be made: - LD_LIBRARY_PATH=... --> PATH=$PATH:..., because cygwin uses PATH to look for .dlls My question: I think there have to be made more configurations than I did to create the boost.python-stuff under cygwin. Where have they to be done, and what? (I already configured environment variables like GCC_ROOT_DIRECTORY, GXX, PYTHON_ROOT, ...etc...) Any suggestions are welcome! Please send a copy of your answer to schnoerr(a)mailzone.com Thank you in advance, Claudius --------------------------------------------------------- This Mail has been checked for Viruses Attention: Encrypted mails can NOT be checked! ** Diese Mail wurde auf Viren geprueft Hinweis: Verschluesselte mails koennen NICHT auf Viren geprueft werden! ---------------------------------------------------------

2 1

Wrapping a std::list with boost.python
by jefflholle 03 Nov '02

03 Nov '02

I've just started experimenting with version 2 of boost.python. In iterator.cpp, a std::list is wrapped using following code: typedef std::list<int> list_int; void push_back(list_int& x, int y) { x.push_back(y); } int back(list_int& x) { return x.back(); } . . . class_<list_int>("list_int") .def("push_back", push_back) .def("back", back) .def("__iter__", iterator<list_int>()) ; Is it possible to use the container methods instead of user defined functions? I've tried the code: class_<list_int>("list_int") .def("push_back", &list_int::push_back) .def("back", &list_int::back) .def("__iter__", iterator<list_int>()) ; This doesn't work. Am what I'm tried to do possible? If so, how?

2 1

[BGL] How to prune a BFS or exit a BFS
by kweeheong 01 Nov '02

01 Nov '02

I have a custom BFS visitor used to traverse a graph. Is there a built-in way to - prune off a vertex's descendants from the search - exit a BFS These ( pruning and terminating ) are separate situations. I believe the following will work; however, I do not know how to access the relevant data structures. - To prune off a vertex's descendents from the search In the custom BFS visitor's discover_vertex event, set the color of all its adjacent descendants to "black". - To exit a BFS In the custom BFS visitor's discover_vertex event, once the required vertex is found, empty the queue of vertices. How can I access a vertex's color and a BFS's queue? Or is there a better way?

2 2

How to pass result of boost::bind to arg of template function ?
by hugo duncan 31 Oct '02

31 Oct '02

Hi, I want to pass the result of a boost::bind as an argument of a templated function of a class, and am struggling to find a signature that will let me do this. Is this possible? if so what signature should the function have ? Any help much apreciated Hugo #include "boost/function/function1.hpp" #include "boost/bind.hpp" class another_class {}; class my_class { public: typedef another_class ObjectType; //! this works fine passing a boost::function object template <class ReturnType> void add(const boost::function1<ReturnType,ObjectType>& arg) { boost::function1<ReturnType,ObjectType> fn_obj=arg; } //! this should work when passed the result of a boost::bind template <class ReturnType> void add(?what goes here? & arg) { function1<ReturnType,ObjectType> fn_obj(arg); } }; int fn(another_class,int) { return 1; } int main(int, char**) { my_class c; c.add(boost::bind(&fn,_1,1)); }

2 1

[bgl] breadth_first_search for shortest paths (fwd)
by Joel Young 31 Oct '02

31 Oct '02

Dear Jeremy, et al, I am trying to implement a shortest paths algorithm on a directed graph. As I have unit edge weights, I would rather use breadth_first_search rather than dijkstra. // Is this a good candidate for addition? template <class Map, class Tag> struct vertex_marker : public boost::base_visitor<vertex_marker<Map,Tag> > { typedef Tag event_filter; vertex_marker(Map p_map,int p_val) : m_map(p_map),m_val(p_val) { } template <class Vertex, class Graph> void operator()(Vertex v,const Graph&) { boost::put(m_map,v,m_val); } Map m_map; int m_val; }; template <class Map, class Tag> vertex_marker<Map,Tag> mark_vertices(Map p_map, Tag, int p_v) { return vertex_marker<Map,Tag>(p_map,p_v); } boost::breadth_first_search( mygraph, rootnode, boost::visitor(boost::make_bfs_visitor( std::make_pair( boost::record_distances( boost::get(boost::vertex_distance,mygraph), boost::on_tree_edge()) , std::make_pair( mark_vertices( boost::get(boost::vertex_distance,mygraph), boost::on_initialize_vertex(), std::numeric_limits<int>::max()) , mark_vertices( boost::get(boost::vertex_distance,mygraph), boost::on_start_vertex(), 0) ) ) )) ); The problem is that on_start_vertex does not seem to be implemented for breadth_first_search, but it is for depth_first. For dijkstra, the start node seems to be automaticly zeroed. I guess I could mod Am I missing something really obvious here or is there an inconsistency across the algorithms? Shouldn't on_start_vertex be used for all of the graph algorithms? Also, I can't seem to find documentation on neighbor_bfs.hpp Thanks, Joel

2 1

Debug regex++ in VC6
by r_gharavi 31 Oct '02

31 Oct '02

When I build a stand-alone debug xll with regex++ (static linking), Excel refuses to accept it as an addin. It works fine in release mode. Due to reasons beyond my control :-), I am using VC6 STL. Any pointers would be appreciated. Thanks.

1 0

d_heap bug
by Tsvetomir Valtchev 31 Oct '02

31 Oct '02

[I tried to contact the library's author, dietmar.kuehl@claas- solutions.de, but the message bounced back.] Dear Dietmar, I was looking for a better heap class than the one in STL and I was delighted to come across your d_heap class included in the Boost library. Unfortunately, I had a number of problems with it, and I figured you might be interested in some feedback. First, the class didn't compile with VC.NET (and probably won't with VC 6 either). This might be due to non-conformance on the part of Microsoft's compiler and some known limitations with template support, but for some of the issues I think they were due to the non- conformance of the code itself. Second, to my dismay, the code turned out to be seriously flawed. The following simple fragment, for example, causes a crash: THeap::pointer ptrs[10]; ptrs[0] = heap.push(12); ptrs[1] = heap.push(16); heap.remove(ptrs[0]); heap.remove(ptrs[1]); After some debugging and deciphering of the code, I found that the remove() function didn't handle a special case where the node to be 'sifted up' coincided with the last "hole" left in the tree. I think pop() had a similar problem. (In my fixed version, I have expressed pop() in terms of remove(), which resolves the problem and also avoids some code duplication.) I hope some day you get around to publishing an improved version. Another suggestion I have is some way to make sure that the pointer's passed back by client code are valid. Extensive use of assertions throughout the code might also prevent various programming errors. Regards, // Chango V.

1 0

Regex++ and UTF-8
by Gitit 31 Oct '02

31 Oct '02

Hi, We want to use regex++ (version 3.31) with UTF-8 strings. I tried to match a UTF-8 character of 2 bytes to the regex "." and the match failed. It seems regex++ handles these 2 bytes as two separate characters. 1) Is there a "native" way in the regex++ library for using UTF-8 strings? Can we use UTF-8 strings to compare against a compiled regex (the regex is in ASCII only)? Can the regex itself hold UTF-8 characters? 2) Is converting to wchar_t our only option? As far as I understand, wchar_t does not cover the entire range of characters covered by UTF-8, so it may not be enough. Any other ideas? thanks, Gitit.

1 0

Re: [Boost-Users] Re: regex: flag for "global" search?
by dick.bridges＠tais.com 30 Oct '02

30 Oct '02

The boost::regex_search example bumps the start to march through the sub-expressions and the boost::regex_grep examples demonstrate using the 'callback' for each term. I was kinda hoping the library provided a "convenience version" that would take something like "(\\w+)(?:\\.(\\w+))*" and populate the match_results as if the terms had been expanded <e.g.> "(\\w+)(?:\\.(\\w+))?(?:\\. (\\w+))?(?:\\.(\\w+))?"</e.g.> Perhaps to some arbitrary limit? Oh well, given the riches provided, a little while loop now and then is surely a small price to pay. ;) Thanks for the response. I'm continually amazed at the ethos fostered by Boost group members. "Edward Diener" <eddielee@tropic To: boost-users(a)yahoogroups.com soft.com> cc: Sent by: news Subject: [Boost-Users] Re: regex: flag for "global" search? <news(a)main.gmane .org> 10/29/2002 04:54 PM Please respond to Boost-Users Use boost::regex_grep. The boost::regex_search only finds the first match. <dick.bridges(a)tais.com> wrote in message news:OF6181960C.1A0F5C63-ON88256C61.006996C6@tais.net... > I'm trying to capture the sub-expressions in a fqdn (e.g., > one.two.three.com.) One piece of Perl-speak for the expression is: "/ > (\w+)\./g". I've been using boost_search and trying variations on "(?: > (\\w+)\\.)+" but I can't seem to get all the sub-expressions into the > match_results. > > There's got to be a flag I've been overlooking. Any suggestion will be > appreciated. 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

regex: flag for "global" search?
by dick.bridges＠tais.com 30 Oct '02

30 Oct '02

I'm trying to capture the sub-expressions in a fqdn (e.g., one.two.three.com.) One piece of Perl-speak for the expression is: "/ (\w+)\./g". I've been using boost_search and trying variations on "(?: (\\w+)\\.)+" but I can't seem to get all the sub-expressions into the match_results. There's got to be a flag I've been overlooking. Any suggestion will be appreciated. TIA

3 2

Gcc-3.2, statistic_tests.cpp and <limits>
by pcarlini.rm 29 Oct '02

29 Oct '02

Hi, the PR libstdc++/6718 in the Gcc bug database is about a run time problem with this Boost testcase: paolo:~/Programming/c++/boost_1_29_0/libs/random> a.out Confidence level: 0.99; 1-alpha = 0.01; chi_square(19, 36.191) = 0.99 Running tests on minstd_rand KS: 4750* [0] 9500* [0] equidistribution: a.out: statistic_tests.hpp:571: void generic_counter<RandomA ccessContainer>::operator()(int) [with RandomAccessContainer = std::vector<int, std::allocator<int> >] : Assertion `static_cast<unsigned int>(i) < container.size()' failed. Abort According to Nathan Sidwell and Gaby Dos Reis analysis the problem is due to well known issues with numeric_limits<double>::infinity of 3.2's run time library for which unexpectedly Boost provides no work arounds. On the contrary, 2.95.x worked just fine. Please let me know if you need any additional information, ciao, Paolo.

1 1

AW: [Boost-Users] boost::bind problem
by Jasper, Alexander 29 Oct '02

29 Oct '02

-----Ursprüngliche Nachricht----- Von: Mark Snelling [mailto:mark@bakedbeans.com] Gesendet: Dienstag, 29. Oktober 2002 17:44 An: Boost-Users(a)yahoogroups.com Betreff: [Boost-Users] boost::bind problem [...] typedef priority_queue<shared_ptr<Functor>, vector<shared_ptr<Functor> >, bind(less<int(), bind(&Functor::priority, _1), bind(&Functor::priority, _2))> MyQueue; As far as I know you can't call a function in a typedef. bind(..) is a function call returning a predicate. But does s.o. know how to use bind in this manner. I failed to, since the type of what bind returns is far to complex. And it is required if you want to to use bind in conjunction with maps or the priority_queue's. You have to wrap the call in your own predicate. alex

1 0

boost::bind problem
by Mark Snelling 29 Oct '02

29 Oct '02

Hello, I was wondering if anyone out there in Boost land could give me a hand here? Here's the problem: I have a class A: class A { public: A(int i) : _priority(i) {} int priority() {return _priority;} private: int _priority; }; What I want to do is create a std::priority_queue based on boost::shared_ptr<A> and use boost::bind/compose to create the sorting function required by std::priority_queue. However, when I try and typedef the queue (to save a lot of typing) I get compiler errors on VS.NET. using namespace std; using namespace boost; typedef priority_queue<shared_ptr<Functor>, vector<shared_ptr<Functor> >, bind(less<int(), bind(&Functor::priority, _1), bind(&Functor::priority, _2))> MyQueue; Am I going about this the right way? Any help appreciated. TIA Mark.

1 0

Graph library: parallel edges
by Juerg Tschirren 29 Oct '02

29 Oct '02

With the Boost Graph Library, I try do create an undirected graph that does not allow parallel edges, so far without success. Does anybody have a small example that shows how to do this? Juerg

2 1

Graph library: vertex type
by Juerg Tschirren 29 Oct '02

29 Oct '02

In the Boost Graph Library, is it possible to have a custom-defined type for vertices, e.g., I would like to have boost::graph_traits<Graph>::vertex_descriptor map to std::pair<int,int> Can this be done? If yes, how? Juerg

2 1

Re: [Boost-Users] MSVCNT not used anymore?
by dick.bridges＠tais.com 28 Oct '02

28 Oct '02

Thanks! That worked. The MSVCNT example on http://www.boost.org/tools/build/build_system.htm must be left over from a previous version. Appreciate the quick response. sashan <sashang(a)ihug.co To: Boost-Users(a)yahoogroups.com .nz> cc: Subject: Re: [Boost-Users] MSVCNT not used anymore? 10/29/2002 04:20 AM Please respond to Boost-Users dick.bridges(a)tais.com wrote: >I'm having a senior moment. > >MSVCNT is set to C:\Program Files\Microsoft Visual Studio\VC98 and bjam is >invoked with "-sTOOLS=msvc" but the command line that gets invoked is C: >\Program Files\Microsoft Visual C++\VC98\bin\cl and, of course I get: "The >system cannot find the file specified." > >Where's the instructions for compiling with VC6, SP4? > > This is my command line (saved in a batch file): bjam -sTOOLS=msvc -sBUILD=release -sMSVC_ROOT=D:\msvs\VC98 -sVISUALC=D:\msvs\VC98 I don't think MSVCNT is used see http://www.boost.org/tools/build/msvc-tools.html -- P: Egad! You astound me, Brain! B: That's a simple task, Pinky. 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

MSVCNT not used anymore?
by dick.bridges＠tais.com 28 Oct '02

28 Oct '02

I'm having a senior moment. MSVCNT is set to C:\Program Files\Microsoft Visual Studio\VC98 and bjam is invoked with "-sTOOLS=msvc" but the command line that gets invoked is C: \Program Files\Microsoft Visual C++\VC98\bin\cl and, of course I get: "The system cannot find the file specified." Where's the instructions for compiling with VC6, SP4?

2 1

are examples on maual page ready to run?
by J-S Lin 28 Oct '02

28 Oct '02

The error message is as follows, --------------------------------- g:\C++ notes\test_boost\test_matrix.cpp(14) : error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'boost::numeric::ublas::matrix' (or there is no acceptable conversion) with [ T=double, F=boost::numeric::ublas::row_major, A=boost::numeric::ublas::unbounded_array ] ------------------------------ Much appreciated. J-S Lin

2 2

lexical_cast fails to convert std::string to boost::dynamic_bitset<>
by Klaus Nowikow 28 Oct '02

28 Oct '02

Hi! I am trying to convert a string to a boost::dynamic_bitset using boost::lexical_cast, as in this example: template <class Value> bool GetValue(const std::string& str, Value& val) { try { val = boost::lexical_cast<Value>(str); } catch(boost::bad_lexical_cast&) { return false; } return true; } int main() { std::string str = "01"; boost::dynamic_bitset<> bits; if(!GetValue(str, bits)) { [...] } } The lexical_cast always throws an exception. The problem seems to be in lexical_cast.hpp, where a temporary object is created: Target result; if(!(interpreter << arg) || !(interpreter >> result) || !(interpreter >> std::ws).eof()) throw bad_lexical_cast(); and in dynamic_bitset.hpp, where operator>>(std::basic_istream<CharT, Traits>&, dynamic_bitset<Block, Allocator>&) iterates over the bitset using the size() (which is, of course, 0). I sure could solve my particular problem by providing an explicit template instantiation of the GetValue() function, but I don't want to do this because the code is for a library, and I want to reduce references to other libraries to an absolute minimum. Did I miss something here, or is there a workaround for this problem? Regards, Klaus

1 0

Date_Time undefined reference
by David Clark 27 Oct '02

27 Oct '02

Hi, I am having a problem compiling the following example #include "boost/date_time/gregorian/gregorian.hpp" #include "boost/date_time/date_parsing.hpp" #include <iostream> #include <string> int main() { using namespace boost::gregorian; std::string s("2002-10-15"); date d(from_string(s)); std::cout << to_simple_string(d) << std::endl; return 0; }; The linker is complaining about an undefined reference to boost::gregorian::greg_month::as_short_string() const and boost::gregorian::greg_month::as_long_string() const using g++ 3.0.4 g++ test.cpp -o test -DDATE_TIME_INLINE Seems the problem is in the call to to_simple_string(d) Is there something obvious I'm missing here. Thanks David.

6 9

Unexpected result in parsing a regular expression
by abhinkar 27 Oct '02

27 Oct '02

Hi, I recently downloaded the boost regex library and am trying to use the search and replace (regex_merge) API. But I am not getting the expected result. Here is what I am trying to do. I am trying to replace a single quoted string with something. But, the catch here is that the string in single quotes can have zero or many 2 consecutive single quotes. For example: Input (Ignore the angle brackets>: <foo='string with '' consecutive '' single ''quotes' bar='string with no single quotes'> To be replaced by 'XXX'. So the output that I want: <foo=XXX bar=XXX> Here is the regular expression that I wrote in Perl: /(\'[^']*(\'\')*[^']*\')/ I get the expected result in Perl. So, to test this with regex library I wrote a sample program to use the regex_merge API and try the replace functionality. ---------------------------replace.cc-------------------------------- #include <boost/regex.hpp> #include <string> #include <iostream> #include <sstream> #include <iterator> using namespace std; using namespace boost; const std::string formatstr("XXX"); std::string processexp(string resp) { regex expression("(\'[^']*(\'\')*[^']*\')"); std::string result; std::ostringstream t; std::ostream_iterator<char, char> oi(t); cout << "Response:" << resp << endl; result = boost::regex_merge(resp, expression, formatstr, boost::format_all); return result; } int main(int argc) { std::string res; res = processexp("foo='string with '' consecutive '' single ''quotes' bar='string with no single quotes'"); cout << "results=" << res << endl; return 0; } --------------------------------------------------------------------- The output I get is: foo=REPLACEDREPLACED bar=REPLACED I tried several ways, but couldn't get the regular expression to work to return the expected result. I WOULD really appreciate if someone could help me. Thanks in advance, Sameer

2 1

vecS versus listS
by aaronyinyong 26 Oct '02

26 Oct '02

compare the following codes: 1.First I create Graph using vecS parameter: typedef boost::adjacency_list<vecS,vecS,directedS,VertexProperty,EdgeProperty> Graph; ..... E edge_array[num_edges]={E(0,1),E(0,2),E(0,3),E(2,3)}; boost::add_edge(edge_array[i].first,edge_array[i].second,g); ..... This is OK! 2.Then I changed the parameter "vecS" to "listS". typedef boost::adjacency_list<listS,listS,directedS,VertexProperty,EdgePropert y> Graph; ..... E edge_array[num_edges]={E(0,1),E(0,2),E(0,3),E(2,3)}; boost::add_edge(edge_array[i].first,edge_array[i].second,g); It can't be compiled.The VC7 tells me "int can't be converted to void*". So what's wrong? Is there any difference which could be caused by "vecS" and "listS"?

2 1

[BGL] Making GraphvizDigraph bidirectional
by kweeheong 26 Oct '02

26 Oct '02

Hi, For convenience, I am using Graphviz digraphs, reading them into BGL, running my algorithms and writing them out to view the results (with Graphviz dotty ). My compiling environment is VC6. After some compilation failures, I realized that Graphviz digraphs did not support in_edges and other functionality of the bidirectional graphs. Graphviz digraphs is currently defined in graphviz.hpp as : typedef subgraph<adjacency_list<boost::vecS, boost::vecS, boost::directedS, GraphvizVertexProperty, GraphvizEdgeProperty, GraphvizGraphProperty> > GraphvizDigraph; There are 2 potential solutions I see ( there may be others ): Solution 1 : ------------ - Read in Graphviz digraph and then copy it into a working bidirectional graph to run the algorithms. - Copy back to Graphviz digraph to view the results. Solution 2 : ------------ - Change the definition of GraphvizDigraph to : typedef subgraph<adjacency_list<boost::vecS, boost::vecS, boost::bidirectonalS, GraphvizVertexProperty, GraphvizEdgeProperty, GraphvizGraphProperty> > GraphvizDigraph; - Recompile bglviz.lib - Now GraphvizDigraph is bidirectional I prefer Solution 2 because it leverages the generic way that BGL has been written. I am able to rebuild bglviz.lib and my minimal testing shows the bidrectional GraphvizDigraph seems to work so far. I would like feedback whether there are any gotchas with Solution 2. Thanks,

2 1

RE: [Boost-Users] are examples on maual page ready to run?
by Mark Storer 25 Oct '02

25 Oct '02

Which error? What's the compiler saying? We (okay: I) need more info for a proper diagnosis. --Mark Storer Software Engineer Cardiff Software #include <disclaimer> typedef std::disclaimer<Cardiff> Discard;

1 0

are examples on maual page ready to run?
by J-S Lin 25 Oct '02

25 Oct '02

I just download boost and tried to get a hang of it by running examples out of the doc page. But I am not sure if these examples are ready to run or simply like a pseudo-code? A point in the case: This simple matrix example int main () { using namespace boost::numeric::ublas; matrix<double> m (3, 3); for (int i = 0; i < m.size1 (); ++ i) for (int j = 0; j < m.size2 (); ++ j) m (i, j) = 3 * i + j; std::cout << m << std::endl; } I copied it and added the following includes: #include <boost/numeric/ublas/matrix.hpp> #include <iostream> But the compiler (VC7) flag an error on cout. So is this line " std::cout << m << std::endl;" supposed to work, or it is a pseudo-code. Thanks. J-S Lin

1 0

How do I use boost::multi_array with a templated argument?
by Björn Lindberg 25 Oct '02

25 Oct '02

I cannot get the code below to compile with g++-3.2 on GNU/Linux. The error message is: exempel.cpp: In member function `void functor<T>::operator()() [with T = P]': exempel.cpp:26: instantiated from here exempel.cpp:18: `nodetab' has incomplete type exempel.cpp:18: confused by earlier errors, bailing out Since everything is visible at compile time, I can't understand why I'm getting this error message, or what to do about it. ------------- #include <boost/multi_array.hpp> struct P {}; template<typename T> struct functor { typedef boost::multi_array<T, 3> table_t; typedef typename table_t::array_view<2>::type nodetab_t; typedef typename table_t::index_range range; void operator()() { table_t table(boost::extents[5][6][7]); nodetab_t nodetab = table[boost::indices[1][range()][range()]]; } }; int main() { functor vis; vis(); return 0; } ------------- Björn

1 0

Borland 6 Graph example 1
by chongwhite001 25 Oct '02

25 Oct '02

Hi All, I am attempting to run the 1st example (file dependancy) of Boost Graph library with Borland C++Builder 6. It compiles ok but crashes when run in exception.hpp with a call, or rather THROW to negative_edge exception. If anyone can provide any light into this I would be most grateful. (details below) Thanks Christian _________________________________________________________ Fault occurs in: dijkstra_shortest_paths.hpp: void examine_edge(Edge e, Graph& g) { if (m_compare(get(m_weight, e), m_zero)) throw negative_edge(); m_vis.examine_edge(e, g); } The actual fault is in exception.hpp at the point: struct negative_edge : public bad_graph { negative_edge() : bad_graph("The graph may not contain an edge with negative weight."){ } }; The error is: --------------------------- Debugger Exception Notification --------------------------- Project Boost_Ex1_Console.exe raised exception class boost::negative_edge with message 'Exception Object Address: 0x896912'. Process stopped. Use Step or Run to continue. --------------------------- OK Help ---------------------------

2 3

Fwd: uBLAS vs MTL for sparse matrices
by Paul C. Leopardi 25 Oct '02

25 Oct '02

Hi, I posted the following message to boost and have so far had no response. Maybe boost-users is the correct mailing list? Hi, Thanks to Joerg Walter's original conversion of GluCat ( http://glucat.sf.net ) to uBLAS, I have fairly painlessly been able to get GluCat going with the version of uBLAS now promoted to Boost. I'm using sparse matrices: boost::numeric::ublas::sparse_matrix< Scalar_T, boost::numeric::ublas::row_major> and comparing performance to MTL: mtl::matrix< Scalar_T, mtl::rectangle<>, mtl::compressed<>, mtl::row_major >::type The operation I'm performing is quite complicated. Basically, I am generating a large number of sparse matrices, and computing the inner product of a given matrix with each of these matrices in turn. ( If you have a copy of GluCat, see basis_element() in matrix_multi_imp.h ) Because these sparse matrices have only one non-zero per row, operations on an n x n matrix are typically O(n), and seem to be so using MTL: Size vs speed for MTL: Size Time (ms) 32 10 64 20 128 80 256 160 512 700 But with uBLAS, essentially the same operations seem to be O(n^2): Size Time (ms) Slowdown 32 30 3 64 70 3.5 128 830 10.4 256 1940 12.1 512 31770 45.4 o Is there a more appropriate data type in uBLAS? o Do you have any tips on where to tweak uBLAS to get better (ie. O(n) ) performance? o What is BOOST_UBLAS_USE_CANONICAL_ITERATOR and what effect should it have on performance? Thanks

2 1

assign a scalar to boost::numeric::ublas::matrix?
by Michael Na Li 24 Oct '02

24 Oct '02

Hi, having tried various matrix classes, I was excited to see boost finally includes a "standard" matrix class. Thanks for the good work. I have one question, though. How do I initialize a matrix to a scalar value? There is no constructor of the form 'matrix (nr, nc, value)' nor 'matrix::operator=( T value )'. I think both would be nice to have. Michael -- ---------------------------------------------------------------------------- Michael Na Li Email: lina(a)u.washington.edu Department of Biostatistics, Box 357232 University of Washington, Seattle, WA 98195 ---------------------------------------------------------------------------

1 0

[BUG] Macos.hpp configuration woes
by Bobby Thomale 24 Oct '02

24 Oct '02

Yesterday I was trying to help my wife get the Boost libraries to compile in her application. It reminded me of an issue I thought I brought up a while ago (maybe I forgot) that still exists in the boost Macos.hpp config file. In the MacOS.hpp file, it checks to see if you are compiling a Mach-O target. If you are, it reasons, you must be using the Apple BSD headers as well. This logic is even documented in a comment: // If __MACH__, we're using the BSD standard C library, not the MSL: #if __MACH__ The problem with this is that, starting with CW Pro 8, it is actually possible to build a Mach-O target and use the MSL in place of the BSD libraries. Lots of people are apparently doing this, including my wife. (I am still on CFM and have not made the transition to Mach-o yet, but I will eventually and I will potentially be in the same boat. The newer Carbon APIs are Mach-o only so that is where all the carbon programmers will eventually go, and as long as Codewarrior is around, MSL will be there as an option for people.) There are also people who use other STL implementations, such as STLPORT. When it defines all of the stuff it does in there, for the BSD libraries, the mach-o MSL code does not compile. Instead, I get hundreds of compile errors. The only way I could get this to compile for her was to force it to use the TARGET_CARBON stuff at the bottom, after the #else (meaning "not mach-o"), by commenting the __MACH__ stuff out. Obviously, that was a "see if this is really her problem" solution, also to get her up and running, and not a long-term fix. :-) It worked by the way. The config.hpp stuff seperates out your platform settings from your standard library settings. Is there a reason that standard library implementation-specific settings are being set by platform and binary format? If there is magic that needs to happen that is specific to Apple's BSD headers, shouldn't there maybe be a "BSD.hpp" or even "AppleBSD.hpp" for BOOST_STDLIB_CONFIG instead? Or am I missing something? Anyway. That is just a question/suggestion, take it or leave it. It makes sense that the TARGET_CARBON stuff at the bottom is platform specific, but the stuff above it seems like it should go somewhere else. In any case, whether that stuff is moved or not, something needs to change to alleviate the pain for those using Mach-o and MSL together, because right now boost is broken for those users. (Am I reporting this to the right list by the way?) -- Bobby --------------------------------------------------------------------- Bobby Thomale Senior Software Developer Inoveon Corporation http://www.inoveon.com/ ---------------------------------------------------------------------

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VC++ 6.0 ,SGI STL and Boost
by Joshua 23 Oct '02

23 Oct '02

I'm just trying to include the files for the shared_ptr class and keep having problems. I was able to fix a problem with a duplicate definition of 'max' and 'min' (in suffix.hpp, it was conflicting with a file from the SGI STL implementation) I mainly just commented it out, if someone has a better plan on how to fix it I would love to know how to fix it. I have tried Boost 1.28 and 1.29 and still got the same set of errors. In addition to the 'max' and 'min' conflict I am getting these errors : e:\programming projects\c++ projects\boost_1_28_0\boost\checked_delete.hpp(24) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_28_0\boost\checked_delete.hpp(24) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_28_0\boost\checked_delete.hpp(30) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_28_0\boost\checked_delete.hpp(30) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_28_0\boost\detail\shared_count.hpp(184) : error C2504: 'counted_base' : base class undefined e:\programming projects\c++ projects\boost_1_28_0\boost\detail\shared_count.hpp(206) : see reference to class template instantiation 'detail::counted_base_impl<P,D>' being compiled e:\programming projects\c++ projects\boost_1_28_0\boost\detail\shared_count.hpp(253) : error C2061: syntax error : identifier 'Y' e:\programming projects\c++ projects\boost_1_28_0\boost\detail\shared_count.hpp(254) : error C2065: 'Y' : undeclared identifier e:\programming projects\c++ projects\boost_1_28_0\boost\detail\shared_count.hpp(390) : fatal error C1506: unrecoverable block scoping error So I'm not sure if I'm doing something wrong (like not setting up the include order correctly) or if Microsoft is once again making my life hell. I am being bad and using the __int64 data type but I may need to rethink it and convert it to standard C++ (well sorta standard, I think gcc supports a longlong to get a 64bit int.. if not I may change it around to a bit_vector or something). But if anyone can shed some light on why I'm getting these errors listed above I'd really appreciate it. thanks. Joshua.

2 3

VC++ 6.0 with SGI STL and Boost
by Joshua 23 Oct '02

23 Oct '02

I'm using VC++ 6.0 with the SGI implementation of the STL. I'm trying to use the shared_ptr but when I try to include the <boost/shared_ptr.hpp> file I get about 40 errors. Most are related to errors redefining template functions. Its conflicting with the SGI STL header files but I'm not sure how to fix it. I keep thinking that I need to adjust the include order (Currently the Boost files are first, the the STL, then Microsofts includes. It doesn't matter where the Boost include directory is though I still get the same errors : this is a small sample --------------------Configuration: DryDock - Win32 Debug-------------------- Compiling... AbstractComponent.cpp e:\programming projects\c++ projects\boost_1_29_0\boost\config\suffix.hpp(256) : error C2995: 'min' : template function has already been defined e:\programming projects\c++ projects\drydock\drydock\stl\stl_algobase.h(106) : see declaration of 'min' e:\programming projects\c++ projects\boost_1_29_0\boost\config\suffix.hpp(260) : error C2995: 'max' : template function has already been defined e:\programming projects\c++ projects\drydock\drydock\stl\stl_algobase.h(112) : see declaration of 'max' e:\programming projects\c++ projects\boost_1_29_0\boost\checked_delete.hpp(24) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_29_0\boost\checked_delete.hpp(24) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_29_0\boost\checked_delete.hpp(30) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_29_0\boost\checked_delete.hpp(30) : error C2061: syntax error : identifier 'T' e:\programming projects\c++ projects\boost_1_29_0\boost\detail\shared_count.hpp(213) : error C2504: 'counted_base' : base class undefined e:\programming projects\c++ projects\boost_1_29_0\boost\detail\shared_count.hpp(235) : see reference to class template instantiation 'detail::counted_base_impl<P,D>' being compiled And it goes on like that to a grand total of 40 errors. I know its probably just something like the order of the includes or I need to add something to specify the namespace correctly. Has any tried using this combination of libraries (VC++, SGI STL, Boost) and gotten it to work? Thanks.

2 1

Newbie trying to use multi_array ...
by Jon Pendergrass 23 Oct '02

23 Oct '02

I'm new to Boost, so please excuse my lack of knowledge. I'm trying to use the multi_array class and have hit a small snag. I'd like to have a class with a 4-D array. Initially it won't contain any data. However, Microsoft Visual C++ v6.0 complains about not finding a constructor. I want to do something like this: #include "boost/multi_array.hpp" typedef boost::multi_array<std::complex<double>, 4> t_Array4D; class foobar { t_Array4D ar; }; void foobar::SetValue() { // set extents code // set value this->ar[0][0][0][0] = 2.0; }

2 1

Error in date_time example -- exp-time_periods.html
by David Clark 22 Oct '02

22 Oct '02

date_time/doc/exp-time_periods.html class day_period : public { should be class day_period : public time_period {

1 0

Smart Pointers and Autocomplete
by eldritchshadows 21 Oct '02

21 Oct '02

Has anybody ever found a program which worked under Visual C++ that would list the member functions of the pointers wrapped by smart pointers. An example of what I'm talking about would be Visual Assist (except it doesn't seem to work). It would make life easier. Thanks in advance. Nathan Janken

1 0

Error in date_time example -- exp-print_month.html
by David Clark 21 Oct '02

21 Oct '02

There are two errors in the date_time/doc/exp-print_month.html example. std::cout<<"Enter Year: "; int should be std::cout << "Enter Year: "; int year,month; and //Use the calendar to get the last day of the month int eom_day = gregorian_calendar::end_of_month_day( should be int eom_day = gregorian_calendar::end_of_month_day(year,month);

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[BGL] Why does depth_first_search not accept a source vertex parameter?
by kweeheong 20 Oct '02

20 Oct '02

Hi, I'm just learning about the BGL, and I've been sucessful in compiling and learning with examples on my VC6 Windows machine. I have a newbie question that someone with more knowledge of BGL might be able to answer : Q : Why does depth_first_search not accept a source vertex parameter, while breadth_first_search do? Is this just to be consistent with the historical definition of DFS? However, depth_first_visit and breadth_first_visit both accept a source vertex parameter. It would seem that DFS is more useful ( output is more deterministic ) if the source vertex can be specified, just like BFS. Reference : ( from the online BGL documentation ) template <class VertexListGraph, class P, class T, class R> void breadth_first_search(VertexListGraph& G, typename graph_traits<VertexListGraph>::vertex_descriptor s, const bgl_named_params<P, T, R>& params); template <class IncidenceGraph, class P, class T, class R> void breadth_first_visit(IncidenceGraph& G, typename graph_traits<IncidenceGraph>::vertex_descriptor s, const bgl_named_params<P, T, R>& params); template <class VertexListGraph, class class P, class T, class R> void depth_first_search(VertexListGraph& G, const bgl_named_params<P, T, R>& params); template <class IncidenceGraph, class DFSVisitor, class ColorMap> void depth_first_visit(IncidenceGraph& g, typename graph_traits<IncidenceGraph>::vertex_descriptor s, DFSVisitor& vis, ColorMap color);

1 0

Error in date_time example -- exp-print_holidays.html
by David Clark 20 Oct '02

20 Oct '02

Two errors in date_time/doc/exp-print_holidays.html In function print_date std::cout << d << " [" << d. should be std::cout << d << " [" << d.day_of_week().as_short_string() << "]\n"; and year is not defined in main() std::cout << "Enter Year: "; int should be std::cout << "Enter Year: "; int year;

2 2

A New Boost Mailing List
by Jon Kalb 18 Oct '02

18 Oct '02

As you know there are currently three Boost mailing lists: Boost - the discussion list for Boost library developers Boost-Users - the discussion list for Boost library users Boost-Announce - for library review and release announcements But we feel the need for an additional list. This list, Boost-Interest, will be an announcement list for items of interest to members of the Boost community. We see this as a low volume, moderated list on which commercial announcements are acceptable if relevant. We have written a proposed charter (below), but we invite comments and volunteers to moderate this list. Boost-Interest: Proposed Charter Boost-Interest is a moderated mailing list of announcements of interest to the Boost community. On topic messages will include announcements of books, magazine articles, papers, talks, seminars, products, tools, events, or conferences on advanced uses of C++, generic/generative/meta-programming, and, of course, the Boost libraries. Off topic will be discussions of any kind and job postings. If you are have comments on this list or its charter please send them to either or both Doug and Jon (addresses below). Also contact us if you are interested in moderating this list. Please do not ask for subscription information yet. We will announce details when we know them. -- Doug Gregor <gregod(a)cs.rpi.edu> Jon Kalb <Kalb(a)LibertySoft.com>

2 1

^M
by Felix E. Klee 18 Oct '02

18 Oct '02

Hi, I found that at least part of the Boost code contains DOS style carriage returns. Why is that? This causes parsing errors on UNIX. Felix

1 1

RE: [Boost-Users] Re: Error in Date_Time example - exp-days_alive.html
by Jeff Garland 17 Oct '02

17 Oct '02

David wrote: > I just checked the example code in > libs/date_time/example/gregorian/date_alive.cpp > > the correction should be > > else if (days_alive < date_duration(0)) { Thx -- I'll clean that up. Jeff

1 0

Template class static boost::mutex initialization !?!?!
by Luc Bergeron 17 Oct '02

17 Oct '02

Hello everyone, i'm currently trying to implement a thread safe singleton using template. In the class I need to use a boost::mutex in order to protect access to the singleton pointer. The problem i'm currently encountering is that I need to initialize this static boost::mutex, but how !?!?!?! I tried using a pointer to a mutex and initialize it to null but that didn't work. I also tried to new it in the initialization but that failed too. :( Can someone help me on this one ??? Thanks in advance for any help. Luc. P.S. I'm using boost 1.29 :) P.S.S Here is my current class definition : (A link to where I got this implementation : http://www.drizzle.com/~scottb/publish/gpgems1_singleton.htm) template <typename T> class ThreadSafeSingleton { static T* d_ThreadSafeSingleton; static boost::mutex d_mutex; public: ThreadSafeSingleton() { assert(!d_ThreadSafeSingleton); int offset = (int)(T*)1 - (int)(ThreadSafeSingleton <T>*)(T*)1; d_ThreadSafeSingleton = (T*)((int)this + offset); } ~ThreadSafeSingleton() { assert(d_ThreadSafeSingleton); d_ThreadSafeSingleton = 0; } static T& GetSingleton(void) { boost::mutex::scoped_lock scoped_lock(d_mutex); assert(d_ThreadSafeSingleton); return *d_ThreadSafeSingleton; } static T* GetSingletonPtr(void) { boost::mutex::scoped_lock scoped_lock(d_mutex); return d_ThreadSafeSingleton; } }; template <typename T> T* ThreadSafeSingleton <T>::d_ThreadSafeSingleton = 0;

1 1

RE: [Boost-Users] min & max #undef'd by config.hpp?
by richard_cox＠dell.com 17 Oct '02

17 Oct '02

On 17 October 2002 09:14, Chris Russell [mailto:cdr@encapsule.com] wrote: > > I'm confused. Using MS Visual Studio 6.0 w/the Intel 6.0 > compiler (or the > native VC compiler for that matter) the min and max macros > are defined in > the MS header WINDEF.H. It seems that config.hpp #undef's > these (although I > haven't figured out where or why yet). My environment seems > to be perfectly > happy using std::min/std::max. But what of all these > MS-defined macros that > use the undecorated min/max? I really don't want to go > chasing these down in > the MS + third-party headers if I can avoid it. Will someone > please explain > to me what's going on with config.hpp? There is nothing in windows.h that uses min & max. In fact if you define NOMINMAX *before* you include windows.h they will not be defined. > --- simple example --- > > #include <windows.h> > #include <boost/config.hpp> > #if defined(min) > #pragma message "min is defined" > #else > #pragma message "min not defined" > #endif > #if defined(max) > #pragma message "max is defined" > #else > #pragma message "max not defined" > #endif > int main(int argc, char* argv[]) > { > int a = 10, b = 20; int c = min(a,b); int d = max(a,b); > return 0; > } You either need: using std::min; using std::max; or fully qualify those names... > > Deleting intermediate files and output files for project 'test - Win32 > Debug'. > --------------------Configuration: test - Win32 > Debug-------------------- > Compiling... > StdAfx.cpp > test.cpp > . . . Boost configuring for Intel C++ compiler > min not defined > max not defined > L:\boost\test\test.cpp(24): error: identifier "min" is undefined > int c = min(a,b); ... hence this error, there is no ::min. > L:\boost\test\test.cpp(25): error: identifier "max" is undefined > int d = max(a,b); > ^ Richard Cox Senior Software Developer Dell Technology Online All opinions and statements mine and do not in any way (unless expressly stated) imply anything at all on behalf of my employer

2 1

Trivial doc error in http://boost.org/libs/smart_ptr/shared_ptr.htm
by Smith, Eric V. 17 Oct '02

17 Oct '02

Not sure if this is the right place to send this, but here goes. About half way down the page, "rile" should be "rule".

2 1

how to build boost with special gcc
by wugui 17 Oct '02

17 Oct '02

i install gcc-3.2 in a new directory. pl. /usr/local/gcc-3.2/ how build boost with it. Thanks.

2 1

Can't build library under vc7
by Alexander Semenov 17 Oct '02

17 Oct '02

Hi, I use > cl Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.00.9254 for 80x86 > cd /wrk/sft/boost/libs/python/build > bjam -sTOOLS=vc7 ...found 961 targets... ...updating 21 targets... vc-C++ ..\..\..\libs\python\build\bin\boost_python.dll\vc7\debug\runtime-link-dynam ic\function.obj function.cpp C:\wrk\sft\boost\boost\python\args_fwd.hpp(40) : error C2118: negative subscript or subscript is too large C:\wrk\sft\boost\boost\python\args_fwd.hpp(41) : see reference to class template instantiation 'boost::python::detail::error::more_keywords_than_function_arguments<,>' being compiled etc... Compiling fails on: C:\wrk\sft\boost\boost\python\args_fwd.hpp(40) : error C2118: negative subscript or subscript is too large C:\wrk\sft\boost\boost\python\args_fwd.hpp(41) : see reference to class template instantiation 'boost::python::detail::error::more_keywords_than_function_arguments<,>' being compiled C:\wrk\sft\boost\boost\pending\detail\property.hpp(75) : error C2039: 'result<`template-parameter258'>' : is not a member of 'boost::detail::property_value_end<PropertyList>' C:\wrk\sft\boost\boost\pending\detail\property.hpp(75) : fatal error C1507: previous user errors and subsequent error recovery halt further compilation Alexander Semenov.

2 1

Error in Date_Time example - exp-days_alive.html
by David Clark 17 Oct '02

17 Oct '02

There is an error in the following date_time example: libs/date_time/doc/exp-days_alive.html else if (days_alive < should be else if (days_alive < one_day) {

1 1

64-bit support for integer_traits on MSVC
by John Harris (TT) 17 Oct '02

17 Oct '02

It seems that there should be a way to get 64-bit integer support into integer_traits.hpp on MSVC. It looks like the only real problem is the missing feature of class constants, and the fact that integer_traits is using enums (which can't hold const_max and const_min values). But if there were specializations on the detail::integer_traits_base for MS 64-bit types, the constants could be declared in-class as __int64 but defined out-of-class (still in the header), safely. It's not as pretty as BOOST_STATIC_CONSTANT, but wouldn't it work? john harris trading technologies

1 0

min & max #undef'd by config.hpp?
by Chris Russell 17 Oct '02

17 Oct '02

I'm confused. Using MS Visual Studio 6.0 w/the Intel 6.0 compiler (or the native VC compiler for that matter) the min and max macros are defined in the MS header WINDEF.H. It seems that config.hpp #undef's these (although I haven't figured out where or why yet). My environment seems to be perfectly happy using std::min/std::max. But what of all these MS-defined macros that use the undecorated min/max? I really don't want to go chasing these down in the MS + third-party headers if I can avoid it. Will someone please explain to me what's going on with config.hpp? - Thanks & regards Chris Russell --- simple example --- #include <windows.h> #include <boost/config.hpp> #if defined(min) #pragma message "min is defined" #else #pragma message "min not defined" #endif #if defined(max) #pragma message "max is defined" #else #pragma message "max not defined" #endif int main(int argc, char* argv[]) { int a = 10, b = 20; int c = min(a,b); int d = max(a,b); return 0; } Deleting intermediate files and output files for project 'test - Win32 Debug'. --------------------Configuration: test - Win32 Debug-------------------- Compiling... StdAfx.cpp test.cpp . . . Boost configuring for Intel C++ compiler min not defined max not defined L:\boost\test\test.cpp(24): error: identifier "min" is undefined int c = min(a,b); ^ L:\boost\test\test.cpp(25): error: identifier "max" is undefined int d = max(a,b); ^ compilation aborted for L:\boost\test\test.cpp (code 2) Error executing xicl6.exe. Creating browse info file... BSCMAKE: error BK1506 : cannot open file '.\Debug\test.sbr': No such file or directory Error executing bscmake.exe. test.exe - 3 error(s), 0 warning(s)

1 0

integrating shared_ptr and building with gcc 2.7.2
by Nik Kolev 16 Oct '02

16 Oct '02

Hi everybody: I would like to make some of my classes reference counted, and I like what shared_ptr offers. The problem is (or is it really?) that I am building (have to) with gcc 2.7.2. The gcc.h header file which is part of the shared_ptr library does not like versions of gcc prior to 2.9.0. I would greatly appreciate it if somebody could point out a way to use the boost's shared_ptr technique and build with gcc prior to 2.9 Thanks, Nik

2 2

newbie here. can't get anywhere with the regex search example
by suzanne 16 Oct '02

16 Oct '02

hi all. i'm brand new with this and just trying to figure everything out. i build the regex search example using VC++ 5, but i can't seem to make it 'go'. in debug mode, my argv (the name of a .cpp file) is blank! argc is incremented properly, so it's seeing something. but no value at all for the argv i'm feeding it - just a good old "". i've got to take this thing apart & learn it so i can implement it in a tool i'm building - can anyone help me get started? i want to step through the various examples to learn it. thanks, suzanne

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RE: boost vs. The Lawyers (non-technical)
by Brian Neal 16 Oct '02

16 Oct '02

Thanks for the input so far. I too would like to call for some blanket license that all boost developers agree to (if possible). It looks like I'll be contacting developers individually and trying to get them to sign something for us. Not fun for either side I guess. Thanks, Brian Neal

3 2

[random] Known problems compiling random lib with Dinkumware STL?
by Chris Russell 15 Oct '02

15 Oct '02

I'm using the Intel 6.0 compiler under MS Visual Studio 6.0 SP6 and just attempted to plug the Dinkumware STL distribution into the mix. I ran into a slew of compile-time errors in the random library and am wondering if anyone has seen this before I ride into battle. Thanks - Chris

3 4

RE: [Boost-Users] Re: Type traits direct compiler support
by Beman Dawes 15 Oct '02

15 Oct '02

At 11:11 AM 10/15/2002, scleary(a)jerviswebb.com wrote: >> It is the vagueness of the term "compiler support", which you did not >> alleviate in your answer, which I am trying to clarify. > >"Compiler support" means "anything the compiler can give us so that we can >implement that class correctly". > >It could be a specially-recognized preprocessor define, a quasi-class >(e.g., >SGI's type traits), a pragma, a keyword, or anything else that the compiler >provides. Yes. "Compiler support" can be seen as a courtesy by library experts, so they aren't trying to tell core language experts exactly how to do something. --Beman

2 1

RE: [Boost-Users] Re: Type traits direct compiler support
by Mark Storer 15 Oct '02

15 Oct '02

What exactly can't you do with existing techniques? I was Most Impressed by Modern C++ Design, and I don't recall any limits stated on what was possible... the whole concept is relatively new to me --Mark Storer Software Engineer Cardiff Software #include <disclaimer> typedef std::disclaimer<Cardiff> Discard;

1 0

RE: [Boost-Users] Re: Running the Boost_1_29_0 regression tests
by Beman Dawes 15 Oct '02

15 Oct '02

At 12:02 PM 10/15/2002, Arjun Bijanki wrote: >"David Abrahams" writes: > >> "Arjun Bijanki" <arjunb(a)microsoft.com> writes: > >> > Hi, I'm having trouble running the Boost_1_29_0 regression tests. A >lot >> > >> >> Arjun, >> >> What are you doing to compile/link the tests? >> The supported method uses bjam. Have you tried that? >> If you use the -d+2 option you can look at the command-lines used and >> replicate them in whatever environment you like. >> >> -Dave > >Thanks. Previously, I was using /status/regression.cpp to generate the >status table; I'll try using bjam instead. We probably should have removed regression.cpp from the 1.29.0 release. The thought occurred to me, but that was before we decided to include all the new regression test components in the current CVS main trunk. Now that the main trunk has everything needed for the new tests, there is no reason to keep regression.cpp around. I'll remove it. --Beman

1 0

RE: [Boost-Users] Re: Running the Boost_1_29_0 regression tests
by Arjun Bijanki 15 Oct '02

15 Oct '02

"David Abrahams" writes: > "Arjun Bijanki" <arjunb(a)microsoft.com> writes: > > Hi, I'm having trouble running the Boost_1_29_0 regression tests. A lot > > > > Arjun, > > What are you doing to compile/link the tests? > The supported method uses bjam. Have you tried that? > If you use the -d+2 option you can look at the command-lines used and > replicate them in whatever environment you like. > > -Dave Thanks. Previously, I was using /status/regression.cpp to generate the status table; I'll try using bjam instead. Arjun

1 0

RE: [Boost-Users] Re: Type traits direct compiler support
by scleary＠jerviswebb.com 15 Oct '02

15 Oct '02

> -----Original Message----- > From: Edward Diener [mailto:eddielee@tropicsoft.com] > > > > From: Edward Diener [mailto:eddielee@tropicsoft.com] > > > > > > What does it mean in the type_traits documentation that "direct compiler > > > support for that traits class is required" ? I do not see that terminology > > > explained anywhere and am lost as far as to what it refers. > > > > It means that there is no known way to implement that class (in a > > Standard-compliant, portable manner). > > > > The type traits library is in a rather uncomfortable position, since it is > > essentially trying to add reflection to the C++ language after the fact. > > > > As currently implemented, the type traits library bends over backwards to > > try to provide as much as possible to as many different compilers as > > possible. But the simple fact is that it should not really be a library, > > but a part of the supplied language. > > > > Some type traits classes technically require compiler support. However, > > those classes will all try to take their "best guess" at the correct answer > > -- sometimes defaulting to a "safe" default if they can't figure out the > > correct answer. > > What sort of compiler support is being talked of here, since you mention > that it can't be done in a standard-compliant manner ? Does this mean > looking at preprocessor defines to determine the correct results, or what ? > It is the vagueness of the term "compiler support", which you did not > alleviate in your answer, which I am trying to clarify. "Compiler support" means "anything the compiler can give us so that we can implement that class correctly". It could be a specially-recognized preprocessor define, a quasi-class (e.g., SGI's type traits), a pragma, a keyword, or anything else that the compiler provides. -Steve

1 0

Returning a tokenizer by value
by Brian_X7 15 Oct '02

15 Oct '02

Is there a problem with returning a tokenizer from a function? Here's what I've got: typedef boost::tokenizer< boost::char_separator<char> > tokenizer; tokenizer getTokens( istream& is ) { boost::char_separator<char> sep(",","", boost::keep_empty_tokens); std::string str; getline(is,str,'\n'); tokenizer toks( str, sep ); return toks; } .. tokenizer tokens = getTokens(input); tokenizer::iterator it = tokens.begin(); (*it) now contains garbage, interesting enough, iterating through the rest of the container works. when I move the processing of getTokens into the main code body the first token (*it) is then correct. Am I missing something fundamental here?

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RE: [Boost-Users] Type traits direct compiler support
by scleary＠jerviswebb.com 15 Oct '02

15 Oct '02

> -----Original Message----- > From: Edward Diener [mailto:eddielee@tropicsoft.com] > > What does it mean in the type_traits documentation that "direct compiler > support for that traits class is required" ? I do not see that terminology > explained anywhere and am lost as far as to what it refers. It means that there is no known way to implement that class (in a Standard-compliant, portable manner). The type traits library is in a rather uncomfortable position, since it is essentially trying to add reflection to the C++ language after the fact. As currently implemented, the type traits library bends over backwards to try to provide as much as possible to as many different compilers as possible. But the simple fact is that it should not really be a library, but a part of the supplied language. Some type traits classes technically require compiler support. However, those classes will all try to take their "best guess" at the correct answer -- sometimes defaulting to a "safe" default if they can't figure out the correct answer. -Steve

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[ANN] Quaternions, Octonions and Special Functions: please download from CVS.
by Hubert HOLIN 15 Oct '02

15 Oct '02

Somewhere in the E.U., le 15/10/2002 Bonjour Please note that due to some unfortunate circumstances beyond our control, the quaternion, octonion and special functions libraries which shipped with Boost 1.29.0 were not in the state they were meant to be in. You might want to download new versions of these libraries from the CVS in a couple of days. The version which should be present there adds compatibility with M$VCPP 7, and fixes things which CWPro 8 has broken in some circumstances. In a few days there will be another version with a user-contributed fix for gcc2.95.x and stlport on linux, among other things. Merci Hubert Holin Hubert.Holin(a)Bigfoot.com

1 0

Running the Boost_1_29_0 regression tests
by Arjun Bijanki 14 Oct '02

14 Oct '02

Hi, I'm having trouble running the Boost_1_29_0 regression tests. A lot of tests don't appear to have main() defined. As an example, one of the tests fails with the following: *** libs/utility/ref_test.cpp *** ** Microsoft Visual C++ cl /Feboosttmp.exe /Zc:wchar_t /nologo /Zm400 /MDd /W3 /GR /GX /Zi /Od /GZ /I".." /D "WIN32" /D "_DEBUG" /D "_MBCS" /_CONSOLE" ../libs/utility/ref_test.cpp /link /incremental:no user32.lib ref_test.cpp LINK : fatal error LNK1561: entry point must be defined 0.80 s Return code: 2 Fail libs/utility/ref_test.cpp has the following lines: #define BOOST_INCLUDE_MAIN #include <boost/test/test_tools.hpp> But this doesn't seem to define a main() function like it did in Boost_1_28_0. Do I need to do some different kind of installation for Boost_1_29_0, or did I pick up wrong headers, or is this function missing? I downloaded Boost_1_29_0 from: http://boost.sourceforge.net/release/boost_1_29_0.zip Thanks! Arjun Bijanki Microsoft Visual C++

2 1

Formal Review: The Spirit Parser Framework.
by John Maddock 14 Oct '02

14 Oct '02

The formal review for the Spirit Parser Framework begins today, and runs until the end of Sunday 20th October. Discussion should take place on the main boost developer list (boost(a)lists.boost.org) please state in your review whether you think the framework should be accepted into boost or not. The framework can be downloaded from: http://spirit.sourceforge.net/index.php?doc=download/v1_5.html Synopsis: ~~~~~~ Spirit is an object oriented recursive descent parser generator framework implemented using template meta-programming techniques. Expression templates allow us to approximate the syntax of Extended Backus Normal Form (EBNF) completely in C++. Parser objects are composed through operator overloading and the result is a backtracking LL(inf) parser that is capable of parsing rather ambiguous grammars. The Spirit framework enables a target grammar to be written exclusively in C++. Inline EBNF grammar specifications can mix freely with other C++ code and, thanks to the generative power of C++ templates, are immediately executable. In retrospect, conventional compiler-compilers or parser-generators have to perform an additional translation step from the source EBNF code to C or C++ code. Regards, John Maddock (Spirit review manager). http://ourworld.compuserve.com/homepages/john_maddock/index.htm

2 1

Type traits direct compiler support
by Edward Diener 14 Oct '02

14 Oct '02

What does it mean in the type_traits documentation that "direct compiler support for that traits class is required" ? I do not see that terminology explained anywhere and am lost as far as to what it refers.

1 0

RedHat 7.3
by S. Scott Collis 14 Oct '02

14 Oct '02

I appologize if this has been addressed before. I did a quick search of the of the new group and didn't find anything. I just tried to port a code that uses Boost to a new computer loaded with RedHat 7.3. It seems that in 7.3 the /usr/include/asm/atomic.h header is different and generates a warning (i.e. #warning Using kernel header in userland program. BAD! instead of supplying routines like atomic_add and atomin_sub that are apparently required by Boost for the shared_ptr implementation. I ended up replacing this 7.3 header with one from 7.1 and this fixed the problem, but if anyone has a better solution, I would appreciate it. Thanks, Scott -- ===================================================================== Dr. Scott Collis, Asst. Prof. | Tel: (713) 348-3617 Dept. of Mechanical Engineering | Fax: (713) 348-5423 and Materials Science - MS 321 | Rice University | Email: collis(a)rice.edu Houston, TX 77005-1892 | http://mems.rice.edu/~collis =====================================================================

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d:\boost\boost_1_29_0\libs\thread\src\thread.cpp(107) : error C2065: '_beginthre
by satya_vajja 13 Oct '02

13 Oct '02

Hello, I am getting the following error while i compile boost thread library under VC++ 6.0. Could any of you please help me out. d:\boost\boost_1_29_0\libs\thread\src\thread.cpp(107) : error C2065: '_beginthreadex' : undeclared identifier When i define _MT compile flag the compiling error goes off but i get lot of linker errors. satya_vajja(a)yahoo.com Thanks Satya

3 5

regex questions in 1_29_0 with g++ 3.1.1
by Anibal Jodorcovsky 13 Oct '02

13 Oct '02

Hi all, I've been using regex 3.20 with g++ 2.95.3 with no problems. We're in the process of moving towards g++ 3.1.1 (we have a library we need to use and it core dumps with 2.95.3 due to a bug in the stdc++ that goes with it in ofstream). So, I have g++ 3.1.1 working fine in redhat 6.2. I couldn't find the regex standalone library so I ended up downloading the whole boost suite (1_29_0) and I built only the regex++ library. I have one comment regarding this version (which I don't know what it is BTW. What's the version of regex++ in boost 1_29_0?, I guess it's 3.31). It seems that boost:cmatch doesn't work anymore when doing a regex_search, I ended up modifying boost:cmatch with boost::match_results<std::string::const_iterator>, I hope that's ok. I'm also having some trouble compiling some code but this is a problem with the new STL implementation that ships with g++ 3.1.1 (the v3 STL). I can't seem to find the solution, that's why I'm asking here, if anybody has any pointers I'll be very grateful. Look at what I get: commit.cpp: In function `void findSopInstances(IDB_HANDLE**, const std::vector<CommitSopInfo, std::allocator<CommitSopInfo> >&, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> >&, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> >&)': commit.cpp:737: conversion from `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> > > ' to non-scalar type `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<const CommitSopInfo, std::allocator<const CommitSopInfo> > >' requested commit.cpp:738: no match for `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<const CommitSopInfo, std::allocator<const CommitSopInfo> > >& < __gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> > >' operator commit.cpp:742: cannot convert `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<const CommitSopInfo, std::allocator<const CommitSopInfo> > >' to `const CommitSopInfo*' for argument `2' to `bool haveSopInstance(IDB_HANDLE**, const CommitSopInfo*)' commit.cpp: In function `int buildSopSeq(const std::vector<CommitSopInfo, std::allocator<CommitSopInfo> >&, SQ_TYPE, void***)': commit.cpp:913: conversion from `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> > > ' to non-scalar type `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<const CommitSopInfo, std::allocator<const CommitSopInfo> > >' requested commit.cpp:914: no match for `__gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<const CommitSopInfo, std::allocator<const CommitSopInfo> > >& < __gnu_cxx::__normal_iterator<const CommitSopInfo*, std::vector<CommitSopInfo, std::allocator<CommitSopInfo> > >' operator make: *** [commit.o] Error 1 And the code it complains about is this: static void findSopInstances( IDB_HANDLE** idbHandle, const std::vector<CommitSopInfo>& rSopList, std::vector<CommitSopInfo>& rSuccesses, std::vector<CommitSopInfo>& rFailures ) { static const char * func = "(findSopInstances)"; // Iterate over list of SOP instances for ( std::vector<const CommitSopInfo>::iterator pos = rSopList.begin(); pos < rSopList.end(); pos++ ) { // Test whether we have this instance if ( haveSopInstance( idbHandle, pos ) ) { ...... Where haveSopInstance is defined as: static bool haveSopInstance( IDB_HANDLE** idbHandle, const CommitSopInfo* pSopInfo ) { now, this used to compile fine under g++2.95.3 with its stdc++. I don't see why it's having difficuly converting the interator to the CommitSopInfo*. Any ideas? thanks a lot, -Anibal

2 1

controlling edge sequence during traversal
by Jakub Plichta 11 Oct '02

11 Oct '02

Hello I am using an adjacency list graph. During a dfs traversal I would like to be control the order of edge traversal. Specifically I have an edge property with an index value and I would like to traverse the higher index edges first. I have tried getting the out_edges iterator and resorting the edges base on their index but that does not seem to make any difference. Any suggestions would be very greatly appreciated. Thanks Jakub Plichta [Non-text portions of this message have been removed]

2 1

RE: [Boost-Users] Re: boost vs. The Lawyers (non-technical)
by Elliot Murphy 11 Oct '02

11 Oct '02

That would be helpful. Some of my colleagues have had terribly frustrating experiences trying to get our lawyers to approve the use of various boost libraries. The lawyers don't seem to like the idea of going into every source file to read a license agreement. -elliot -----Original Message----- From: James Curran/MVP [mailto:jamescurran@mvps.org] Sent: Thursday, October 10, 2002 9:58 AM To: boost-users(a)yahoogroups.com Subject: [Boost-Users] Re: boost vs. The Lawyers (non-technical) "Douglas Gregor" <gregod(a)cs.rpi.edu> wrote in message news:200210090000.23639.gregod@cs.rpi.edu... > Each Boost library has its own license that _must_ meet those requirements. Of > course, that won't satisfy the lawyers, so you'll probably have to send them > the individual library licenses for approval. > > We really could do much better in this area: at the very least, we could > provide a comprehensive list of the licenses for each library. Perhaps we should add to our "standard" a requirement that a printable license page by included with each libraries' documentation (with one or more "fill-in-the-blank" templates/samples available on www.boost.org) -- Truth, James Curran www.NovelTheory.com (Personal) www.NJTheater.com (Professional) www.aurora-inc.com (Day job) Yahoo! Groups Sponsor ADVERTISEMENT 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 the Yahoo! Terms of Service.

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RE: [Boost-Users] Problem with boost::any.
by Jim.Hyslop 11 Oct '02

11 Oct '02

Luc Bergeron [mailto:bluc@videotron.ca] wrote: > Greets, > > I'm trying to use the boost::any component but i'm having > problem with > it !!! I'm using it because I need a way to store parameters of > different type. That real fine but I can't retrieve the value > from the > boost::any. This is what i've tried : > > std::string GetStringFromAny(const boost::any& val) const > { > std::string strVal; > try > { > strVal = boost::any_cast<std::string>(val); > } > catch(boost::bad_any_cast &err) > { > std::cerr << err.what() << std::endl; > return ""; > } > return strVal; > } > > But I always have a bad_any_cast exception. From the > documentation, at > leats what I understand of it, "If passed a value or reference, it > returns a copy of the value content if successful". Can > someone point me > in the right direction as to how can I extract the value within a > boost::any type, I think i'm lost !!! :) The following program works for me, without any error (using MSVC6): #include <boost/any.hpp> #include <string> #include <iostream> std::string GetStringFromAny(const boost::any& val) { std::string strVal; try { strVal = boost::any_cast<std::string>(val); } catch(boost::bad_any_cast &err) { std::cerr << err.what() << std::endl; return ""; } return strVal; } int main() { boost::any anAny( std::string("Hello, world") ); std::string converted = GetStringFromAny( anAny ); std::cout << "Converted: [" << converted << "]" << std::endl; } The output, as I expected, was: Converted: [Hello, world] Note that if I add more to main: int main() { boost::any anAny( std::string("Hello, world") ); std::string converted = GetStringFromAny( anAny ); std::cout << "Converted: [" << converted << "]" << std::endl; anAny = 23; converted = GetStringFromAny( anAny ); std::cout << "Converted: [" << converted << "]" << std::endl; } the second conversion fails. The conversion will only succeed if the type that boost::any currently holds can be implicitly converted into the type you want to retrieve. If you want to convert from (for example) an int to a string, you'll need boost::lexical_cast. -- Jim -- Jim

1 0

Problem with boost::any.
by Luc Bergeron 11 Oct '02

11 Oct '02

Greets, I'm trying to use the boost::any component but i'm having problem with it !!! I'm using it because I need a way to store parameters of different type. That real fine but I can't retrieve the value from the boost::any. This is what i've tried : std::string GetStringFromAny(const boost::any& val) const { std::string strVal; try { strVal = boost::any_cast<std::string>(val); } catch(boost::bad_any_cast &err) { std::cerr << err.what() << std::endl; return ""; } return strVal; } But I always have a bad_any_cast exception. From the documentation, at leats what I understand of it, "If passed a value or reference, it returns a copy of the value content if successful". Can someone point me in the right direction as to how can I extract the value within a boost::any type, I think i'm lost !!! :) Thanks in advance for any help. Luc.

2 1

Possible bug in boost_1_28
by Christopher Henrich 11 Oct '02

11 Oct '02

This bug comes up when I try to include <boost/array.hpp> in certain CodeWarrior projects. (CodeWarrior 8.0, running under Mac OS 10.1.5 on G3 "beige tower") If I initialize the project with stationery "C++ Console Mach-O", and I change HelloWorld.cp to include <boost/array.hpp>, then I get this error message: Error: undefined identifier 'ptrdiff_t' suffix.hpp line 204 included from config.hpp: 57 array.hpp:27 HelloWorld.cp: 10 If I initialize with PowerPlant stationery, I do not have this problem. Chris Henrich

6 6

BOOST regex problem using Libarys with Borland Builder 4
by Alastair 11 Oct '02

11 Oct '02

Hi I have just found out about the boost library's so I am new to them. I am trying to use the regex within a VCL Borland Builder 4. I have followed the installation. and tried a given example. I found that the example works well for a console program but for a windows program it seems to crash with the message. EAccessViolation with message ŽAccess violation at address 0040987B. Read address 00000032. I have compiled both within the Borland IDE and I believe that I don't have to do anything and that the IDE and Library will automatically configure itself. What am I doing wrong? Thanks in advance Alastair

2 1

Thread Lib Build errors in xtime.cpp
by Glenn Thorne 10 Oct '02

10 Oct '02

I'm getting the following errors when trying to build Boost using the Intel C++ v6.0 compiler. The build completes as expected with msvc. Is there a problem with boost::uint64_t in this configuration or am I missing a setting somewhere? Any help will be appreciated. Thanks! Glenn ******** C:\boost_1_28_0>set INTELC="C:\Program Files\Intel\Compiler60\IA32" C:\boost_1_28_0>bjam "-sTOOLS=intel-win32" ...found 330 targets... ...updating 12 targets... vc-C++ libs\thread\build\bin\libboost_thread.lib\intel-win32\debug\runtime-link- static\threading-multi\xtime.obj xtime.cpp libs\thread\build\../src\xtime.cpp(80): error: namespace "boost" has no member " uint64_t" const boost::uint64_t TIMESPEC_TO_FILETIME_OFFSET = ((boost::uint64_t) 27111902UL << 32) + (boost::uint64_t)3577643008UL; ^ libs\thread\build\../src\xtime.cpp(80): error: namespace "boost" has no member " uint64_t" const boost::uint64_t TIMESPEC_TO_FILETIME_OFFSET = ((boost::uint64_t) 27111902UL << 32) + (boost::uint64_t)3577643008UL; ^ libs\thread\build\../src\xtime.cpp(80): error: expected a ")" const boost::uint64_t TIMESPEC_TO_FILETIME_OFFSET = ((boost::uint64_t) 27111902UL << 32) + (boost::uint64_t)3577643008UL; ^ libs\thread\build\../src\xtime.cpp(80): error: namespace "boost" has no member " uint64_t" const boost::uint64_t TIMESPEC_TO_FILETIME_OFFSET = ((boost::uint64_t) 27111902UL << 32) + (boost::uint64_t)3577643008UL; ^ libs\thread\build\../src\xtime.cpp(80): error: expected a ";" const boost::uint64_t TIMESPEC_TO_FILETIME_OFFSET = ((boost::uint64_t) 27111902UL << 32) + (boost::uint64_t)3577643008UL; ^ compilation aborted for libs\thread\build\../src\xtime.cpp (code 2) "C:\Program Files\Intel\Compiler60\IA32/bin/icl" /Zm400 -nologo -GX -c /Z 7 /Od /Ob0 /GX /GR MTd -I"libs\thread\build" -I"C:\boost_1_28_0" -I"C:\PROGR A~1\MICROS~3\VC98\include" -I"../include" -Fo"libs\thread\build\bin\libboo st_t hread.lib\intel-win32\debug\runtime-link-static\threading-multi\xtime.obj" -Tp" libs\thread\build\../src\xtime.cpp" ...failed vc-C++ libs\thread\build\bin\libboost_thread.lib\intel-win32\debug\run time-link-static\threading-multi\xtime.obj... ...skipped <libs!thread!build\libboost_thread.lib\intel-win32\debug\runtime-link -static\threading-multi>libboost_thread.CMD for lack of <libs!thread!build\libbo ost_thread.lib\intel-win32\debug\runtime-link-static\threading-multi>xtime.o bj.. . ...skipped <libs!thread!build\libboost_thread.lib\intel-win32\debug\runtime-link -static\threading-multi>libboost_thread.lib for lack of <libs!thread!build\libbo ost_thread.lib\intel-win32\debug\runtime-link-static\threading-multi>xtime.o bj.. . ********

1 0

CVS fails to build
by Björn Lindberg 10 Oct '02

10 Oct '02

Boost CVS isn't working for me right now. When I try to build programs against it I get /home/compbio/d95-bli/include/boost/preprocessor/cat.hpp:18:49: boost/preprocessor/config/config.hpp: Filen eller katalogen finns inte /home/compbio/d95-bli/include/boost/preprocessor/cat.hpp:22:28: missing binary operator before '(' /home/compbio/d95-bli/include/boost/preprocessor/cat.hpp:29:28: missing binary operator before '(' ... Is it (a) a bug, or (b) me doing something wrong, or (c) something else? I am running g++-3.2 on GNU/Linux. Björn

1 0

boost vs. The Lawyers (non-technical)
by Brian Neal 10 Oct '02

10 Oct '02

I hope this is appropriate for this mailing list... I am a software engineer and our development team loves boost. However, I can already see a coming battle with our company lawyers trying to convince them to let us use boost in our software. We informally talked with one of our software quality engineers. He said their major concern would be assuring that we had permission to use the boost software. In other words, how would we know that the boost developers had permission to release their libraries so that anyone could use it? He also thought we would need something in writing to this effect. Since their isn't any official boost organization, I am getting scared already. I am not a lawyer, nor do I play one on TV, but I would like to hear from any boost developer or user who has experiences in dealing with this nonsense. 1) How did you get your company lawyers off your backs and let you use boost? 2) Should there be (is there?) a central boost license that all boost libraries have that we can point our lawyers at, instead of going to each and every boost developer to get permission to use his/her library? 3) What has been your experience in this situation? Its ironic that something as wonderful as boost, which gives us so much productivity (and that savings is passed along to our customers) could be considered so dangerous by our lawyers. Again, if this is not appropriate or has been rehashed to death I apologize. If that is the case, please email me off list. I'll collect the responses and give them to anyone who is interested. Thanks, Brian Neal

4 3

tuple vs SGI/MIPSPro
by Kevin Wheatley 10 Oct '02

10 Oct '02

Hi, I'm starting to get to grips with boost and in particular on the SGI platform. I was trying to use the boost::tuples and found that with the SGI compiler v7.3.1.3m I was getting the following error CC -LANG:std -I/images/src/boost/from_cvs/boost -I/images/src/boost/from_cvs/boost/boost/compatibility/cpp_c_headers/ -o tupple tupple.cpp cc-1239 CC: ERROR File = /images/src/boost/from_cvs/boost/boost/tuple/tuple_io.hpp, Line = 113 "close" is ambiguous. case close : c = i.widen(')'); break; ^ A template was detected during header processing. instantiation of "char boost::tuples::detail::format_info::get_manipulator(std:: basic_ios<char, std::char_traits<char>> &, boost::tuples::detail::format_info::manipulator_type)" at line 437 instantiation of "std::basic_istream<char, std::char_traits<char>> &boost::tuples::detail::extract_and_check_delimiter(std:: basic_istream<char, std::char_traits<char>> &, boost::tuples::detail::format_info::manipulator_type)" at line 511 instantiation of "std::basic_istream<char, std::char_traits<char>> &boost::tuples::operator>>(std::basic_istream<char, std::char_traits<char>> &, boost::tuples::cons<double, boost::tuples::detail::map_tuple_to_cons<double, double, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>::type> &)" at line 630 of "/usr/include/CC/stl_iterator.h" instantiation of "void std::istream_iterator<density, char, std::char_traits<char>, ptrdiff_t>::_M_read()" at line 604 of "/usr/include/CC/stl_iterator.h" instantiation of "std::istream_iterator<density, char, std::char_traits<char>, ptrdiff_t>::istream_iterator(std::istream_iterator<densit y, char, std::char_traits<char>, ptrdiff_t>::istream_type &)" at line 19 of "tupple.cpp" I'm working with the code from CVS because it compiled better on the SGI, I looked at the code, and basically I think it's getting confused due to my test program including a "using namespace std;" so I modified the tuple_io.hpp to specifically mention detail::format_info::close rather than the bare close and then my example works (I also made explicit the other cases of the switch statement). Is there a more recomended way of doing this? Almost everywhere else in that file the full specification of the enum is given. My code is something like: #include <vector> #include <iostream> #include <algorithm> #include <numeric> #include <iterator> #include "boost/tuple/tuple.hpp" #include "boost/tuple/tuple_comparison.hpp" #include "boost/tuple/tuple_io.hpp" using namespace std; using namespace boost::tuples; typedef tuple<double, double, double> density; int main() { vector<density> v; istream_iterator<density> in(cin); istream_iterator<density> eos; ostream_iterator<density> out(cout); density total; copy(in, eos, back_inserter(v)); copy(v.begin(), v.end(), out); cout << endl; return 0; } Thanks Kevin -- | Kevin Wheatley | These are the opinions of | | Senior Do-er of Technical Things | nobody and are not shared | | Cinesite (Europe) Ltd | by my employers |

1 0

Building regex on AIX w VisualAge
by Tim Daplyn 10 Oct '02

10 Oct '02

Can anyone assist me with this? I've tried every compiler option I can think of combined with disabling BOOST support for a whole bunch of stuff and I still can't get this library to build on AIX. There are just too many compile errors, and I was really hoping I wouldn't have to go modifying the source.

2 1

How to Create Calculated Internal Properties?
by Phillip Ratzloff 09 Oct '02

09 Oct '02

I wish to create an internal calculated property that is derived from existing properties in a vertex or edge. Id also like to be able to access it like any other internal property. For instance, I want a vertex property called weight_sum that would sum the weights for all the out edges and return the answer. I want to be able to use a statement "get(vertex_weight_sum,G,v)" to get the value. Later on, I may decide that I want to cache the value on the vertex (like a normal property) and existing code should work without change. I have been unable to figure out any template class specializations to do this. Additionally, if I try to define the property using the property<> template in the graph declaration it reserves storage for the property, which is undesired. Am I missing something? Is there a way to define a calculated internal property that doesnt reserve storage?

1 0

using weak_ptr and shared_ptr for singleton
by Stephan Born 09 Oct '02

09 Oct '02

Hello! I do some experiments on shared_ptr and weak_ptr. So I tried to use them for a singleton-class, which does not need an explicit singleton::release_instance method. The singleton-instance will be destroyed everytime the last external shared_ptr holding the instance goes out of scope. Is this a valid usage for weak_ptr? Are there any traps I do not see using these smart_ptrs in this context? The drawback of using shared_ptr with singleton is the need for a public destructor. But this is dangerous....it is possible to write singleton::singleton_ptr first_ptr = singleton::instance(); delete first_ptr.get(); Declaring the destructor as private is only possible when defining boost::checked_delete as friend of the singleton-class. ( there is a thread on comp.lang.c++.moderated with the topic 'specialization of function template as friend with MSVC6SP5 not possible' which deals with this problem of friendship... ) But then it is still possible to write the following code singleton::singleton_ptr first_ptr = singleton::instance(); boost:checked_delete( first_ptr.get() ); OK, it's very unlikely to do it by chance, but it is possible. Is there a way to allow destruction of the instance only to shared_ptr? <code> #include <boost/shared_ptr.hpp> #include <boost/weak_ptr.hpp> #include <boost/utility.hpp> class singleton : boost::noncopyable { public: typedef boost::shared_ptr< singleton > singleton_ptr; static singleton_ptr instance() { singleton_ptr tmp; if( s_instance.expired() ) { tmp.reset( new singleton ); s_instance = tmp; } else { tmp = boost::make_shared( s_instance ); } return tmp; } void foo() { // do something i++; } // like to make it private in order to prohibit delete on it, // but boost::shared_ptr<> can't handle it....so sad :( ~singleton(){}; private: typedef boost::weak_ptr< singleton > internal_singleton_ptr; singleton(){}; int i; static internal_singleton_ptr s_instance; }; singleton::internal_singleton_ptr singleton::s_instance; int main() { { singleton::singleton_ptr first_ptr = singleton::instance(); { singleton::singleton_ptr second_ptr = singleton::instance(); second_ptr->foo(); } first_ptr->foo(); } singleton::singleton_ptr another_ptr = singleton::instance(); another_ptr->foo(); return 0; } </code> Regards, Stephan -- --------------------------------------------------------------- Dipl.-Inf. (FH) Stephan Born | beusen Solutions GmbH fon: +49 30 549932-0 | Landsberger Allee 366 fax: +49 30 549932-21 | 12681 Berlin mailto:stephan.born@beusen.de | Germany --------------------------------------------------------------- PGP-Key verfügbar | PGP-Key available ---------------------------------------------------------------

3 6

Regex Access violation in BCB5
by Tim Daplyn 09 Oct '02

09 Oct '02

I've used a previous version of the boost regex library before and have just upgraded to the latest version. Built the libs and dll fine, but now I get a A/V when calling any boost code. I've even set up a vanilla console app with all the Borland default settings and the following code: #include "boost/regex.hpp" int main(int argc, char* argv[]) { boost::wregex regExpr2(L"bill.*"); bool result; result = boost::regex_match(L"freddy", regExpr2); result = boost::regex_match(L"billabong", regExpr2); return 0; } And it blows up on the first regex_match!! I can't figure out what's going on - I know it's linking to the _sdi version of the lib because it complains about it being missing if I remove it, and the dlls are on the path and are loaded as soon as this mini-app starts up. It makes no difference whether I build through the command line or in BCB GUI. Please help!! Thanks, Tim D.

1 0

building smart_ptr as a separate library
by Nik Kolev 07 Oct '02

07 Oct '02

Hi everybody: Is it possible to build/integrate just the smart_ptr part of boost. If yes I would greatly apreciate your suggestions on how this is to be accomplished. Thanks, Nik

2 1

RE: [Boost-Users] Iterator adapters and maps
by scleary＠jerviswebb.com 04 Oct '02

04 Oct '02

I think the problem is in the definition of Select2ndRef; if you use: template<class pair_type> struct Select2ndRef { typedef pair_type argument_type; typedef typename pair_type::second_type result_type; result_type & operator()(pair_type & source) const { return source.second; } }; then your code will compile. This has to do with an unusual meaning of "result_type" for projection iterator adaptors. -Steve

2 1

Use a shared_ptr as a 'backpointer'?
by dick.bridges＠tais.com 04 Oct '02

04 Oct '02

I run into situations where it's useful for an object to have a 'backpointer' to the object instance that created it (example below). Is there a pattern/idiom for doing this using shared_ptr? Or maybe I need to re-think the idea of the backpointer in the first place? class Bar; class Foo { public: Foo(Bar* b) : p(b){} private: Foo() : p(0){} shared_ptr<Bar> p; } class Bar { void doit() { new Foo(???); // <<< new Foo(this) obviously won't work. } }

3 2

[BGL]: 2 desgin questions
by Björn Lindberg 03 Oct '02

03 Oct '02

I have two questions regarding the design of the BGL. I'm interested in this to get a better understanding of the design choices, which influences how I use the BGL and how I'm building on it. 1) Why is a lot of the function arguments made by value rather than reference? As an example, consider the BFS algorithm, where the documentation states that "[1] Since the visitor parameter is passed by value, if your visitor contains state then any changes to the state during the algorithm will be made to a copy of the visitor object, not the visitor object passed in. Therefore you may want the visitor to hold this state by pointer or reference." It would be much easier to use the visitor objects for keeping state throughout the algorithm if it was passed by reference instead. 2) Non-constness. It seems impossible to use BGL together with code that is "const-correct". If, for instance, I have a function implementing some kind of examining algorithm on a graph (so the graph is passed to it as const), and this algorithm uses breadth_first_search with a visitor that doesn't modify the graph, it still can't be const when passed to breadth_first_search. This only leaves the options of either (i) casting away constness in the call, which is bad because it could introduce bugs later on, or (ii) leaving out const altogether which is not good either. Maybe I've just misunderstood something and this is possible, or perhaps it is impossible to implement BGL in this way? Björn

2 2

boost build on redhat7.3
by Alkis Evlogimenos 03 Oct '02

03 Oct '02

Hi, I just compiled boost from cvs. I am using an x86 with redhat linux 7.3. I also have STLport 4.5.3 installed. I compiled against STLport using this command: bjam "-sTOOLS=gcc-stlport" "-sSTLPORT_INCLUDE_DIRECTORY=include/stlport" "-sSTLPORT_LIB_DIRECTORY=lib" "-sSTLPORT_ROOT=/usr" and against gcc using the following: bjam "-sTOOLS=gcc" Both builds finish with success (compiling with j4 leaves 2 targets behind but they succeed after a reinvocation). Now I enter status/ and compile regression using the following: g++ -I.. regression.cpp -o regression Modify compiler.cfg to look like: linux gcc-296 GCC 2.96 g++ -c -Wall -W -ftemplate-depth-30 -I%include %source g++ -o boosttmp.exe -Wall -W -ftemplate-depth-30 -I%include %source -lrt GNU <a href="http://gcc.gnu.org/">GCC</a> 2.96 linux gcc-296-stlport GCC 2.96 STLport 4.5 g++ -c -Wall -W -ftemplate-depth-30 -isystem /usr/include/stlport -I%include %source -lstlport_gcc g++ -o boosttmp.exe -Wall -W -ftemplate-depth-30 -isystem /usr/include/stlport -I%include %source -lrt -lstlport_gcc GNU <a href="http://gcc.gnu.org/">GCC</a> 2.96 <a href="http://www.stlport.org/">STLport</a> 4.5 and finally run regression as follows: ./regression -o cs-rh7.3.html Attached is a gzipped log of the regression run. The text was 429Kb so I didn't paste it to this email :-) It seems that the testing frameworks has some problems (libs/config/test/config_test.cpp fails). Am I doing something wrong here? Any help is appreciated. Thanks, -- Alkis [Non-text portions of this message have been removed]

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[BGL] Daisy chaining algorithms using vistor mechanism?
by Chris Russell 02 Oct '02

02 Oct '02

Still up hacking... Without cluttering the question with a ton of detail, basically I need to perform a DFS on a forest stored in a bidirectionalS adjacency_list and then perform a subgraph traversal in response to each finish_vertex invocation in the visitor. (The idea is to push information down the branches towards the root of a tree in the forest). Calling in_edges(v,g) from within the finish_vertex method in a dfs_visitor will not compile however. This is because the graph is passed by const reference into the visitor method and in_edges requires a non-const graph reference? (this seems similar in spirit to a question I posted a week or two ago about boost::get(some_property, Graph) from within a visitor). Generally, I would like to be able to daisy chain graph algorithms - that is invoke a sub-algorithm from within a visitor method called by a controlling algorithm. This would require that the sub-algorithm not change the graph topology, trample on properties used by its controller (e.g. coloring), or otherwise invalidate vertex descriptors or iterators so some care would need to be taken in designing the sub-algorithm. But it seems like a useful mechanism for extension. Am I missing something about getting at the in_edges given that I'm working with a const graph_t& in the context of the "controlling" DFS' visitor method? Why is this so restrictive? I'm guessing it might have something to do with having multiple copies of vertex and edge iterators floating around but I'm not sure. Will you comment on this please Jeremy? Thank you. - Chris Russell

5 6

RE: [Boost-Users] MPL?
by Mark Storer 02 Oct '02

02 Oct '02

"Modern C++ Design" has a pretty good coverage so far (I'm on chapter 6 out of 11). As for impressing the ladies... well... you could always show them your stamp collection. --Mark Storer Software Engineer Cardiff Software #include <disclaimer> typedef std::disclaimer<Cardiff> Discard; -----Original Message----- From: Jeff Faust [mailto:jeff@opticalres.com] Sent: Wednesday, October 02, 2002 12:37 PM To: Boost-Users(a)yahoogroups.com Subject: RE: [Boost-Users] MPL? Well, I didn't know I needed boost until I saw it. Same for STL several years back. 'Metaprogramming' comes up a lot on the boost list, but I have no understanding about what it's for--what problems it solves. The documentation is sparse. Then this thread comes up and everybody talks about it like it's obvious. I dislike being baffled. But mostly it's curiosity. I need something to talk about at parties and impress the ladies. MPL will do that, right? Right? Hello? Jeff -----Original Message----- From: David B. Held [mailto:dheld@codelogicconsulting.com] Sent: Wednesday, October 02, 2002 12:14 PM To: Boost-Users(a)yahoogroups.com Subject: Re: [Boost-Users] MPL? ----- Original Message ----- From: "Jeff Faust" <jeff(a)opticalres.com> To: <Boost-Users(a)yahoogroups.com> Sent: Wednesday, October 02, 2002 11:32 AM Subject: [Boost-Users] MPL? > [...] > Can anybody explain in English what the following does? I believe that Aleksey posted the runtime pseudo-equivalent. > Posted by David Abrahams on boost developers list: > > Have I mentioned recently how totally cool MPL's lambda facility is? > > I can't believe I can do things like this, even with MSVC6. It makes my > > metaprograms SO much easier to manage! > > mpl::logical_and< > > is_reference_to_class<add_reference<mpl::_> > > > , mpl::logical_not< > > is_reference_to_args<add_reference<mpl::_> > [Aleksey, on 9/27] // "ideal" version, for comparison purposes: // is_reference_to_class( add_reference(_) ) // && !is_reference_to_args( add_reference(_) ) I can't say for sure what the code does myself, but if I could venture a guess, I would say that it's a condition for something else (maybe an iterative algorithm over a type container?) that checks to see if an argument is a reference type of various sorts. Basically, if you don't understand it, in this case, you probably don't need it. ;) I know I don't! Dave 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/ 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] MPL?
by Randy Bowen 02 Oct '02

02 Oct '02

Metaprogramming techniques are discussed pretty thoroughly in Andrei Alexandescru's "Modern C++ Design" and in Czarnecki and Eisenecker's "Generative Programming". --Randy -----Original Message----- From: Jeff Faust [mailto:jeff@opticalres.com] Sent: Wednesday, October 02, 2002 12:37 PM To: Boost-Users(a)yahoogroups.com Subject: RE: [Boost-Users] MPL? Well, I didn't know I needed boost until I saw it. Same for STL several years back. 'Metaprogramming' comes up a lot on the boost list, but I have no understanding about what it's for--what problems it solves. The documentation is sparse. Then this thread comes up and everybody talks about it like it's obvious. I dislike being baffled. But mostly it's curiosity. I need something to talk about at parties and impress the ladies. MPL will do that, right? Right? Hello? Jeff -----Original Message----- From: David B. Held [mailto:dheld@codelogicconsulting.com] Sent: Wednesday, October 02, 2002 12:14 PM To: Boost-Users(a)yahoogroups.com Subject: Re: [Boost-Users] MPL? ----- Original Message ----- From: "Jeff Faust" <jeff(a)opticalres.com> To: <Boost-Users(a)yahoogroups.com> Sent: Wednesday, October 02, 2002 11:32 AM Subject: [Boost-Users] MPL? > [...] > Can anybody explain in English what the following does? I believe that Aleksey posted the runtime pseudo-equivalent. > Posted by David Abrahams on boost developers list: > > Have I mentioned recently how totally cool MPL's lambda facility is? > > I can't believe I can do things like this, even with MSVC6. It makes my > > metaprograms SO much easier to manage! > > mpl::logical_and< > > is_reference_to_class<add_reference<mpl::_> > > > , mpl::logical_not< > > is_reference_to_args<add_reference<mpl::_> > [Aleksey, on 9/27] // "ideal" version, for comparison purposes: // is_reference_to_class( add_reference(_) ) // && !is_reference_to_args( add_reference(_) ) I can't say for sure what the code does myself, but if I could venture a guess, I would say that it's a condition for something else (maybe an iterative algorithm over a type container?) that checks to see if an argument is a reference type of various sorts. Basically, if you don't understand it, in this case, you probably don't need it. ;) I know I don't! Dave 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/ Yahoo! Groups Sponsor ADVERTISEMENT <http://rd.yahoo.com/M=233351.2428261.3848243.2225242/D=egroupweb/S=17050067…> <http://us.adserver.yahoo.com/l?M=233351.2428261.3848243.2225242/D=egroupmai…> 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 the Yahoo! Terms of Service <http://docs.yahoo.com/info/terms/> . [Non-text portions of this message have been removed]

1 0

Iterator adapters and maps
by Alisdair Meredith 02 Oct '02

02 Oct '02

I have a std::map<std::string, MyObject> and want to iterate over it calling several member functions of MyObject. This seems like a good case to learn about transform/projection iterator, but I am having a hard time getting a compiling example. My most recent attempt looks like this: class MyObject { public: void CommitChanges(); void RollbackChanges(); // More implementation details would follow }; typedef std::map<std::string, MyObject> MyMap; typedef MyMap::iterator MyIterator; typedef MyMap::value_type mapped_type; typedef boost::projection_iterator_generator< Select2ndRef<mapped_type>, MyIterator >::type projection; MyMap theMap; projection begin( theMap.begin() ); projection end( theMap.begin() ); for_each( begin, end, mem_fun_ref( MyObject::CommitChanges ) ); I also have the following two templates, although I suspect their equivalent must be lurking in boost somewhere: template<class pair_type> struct Select1stRef { typedef typename pair_type::first_type & result_type; result_type operator()( pair_type &source ) const { return source.first; } }; template<class pair_type> struct Select2ndRef { typedef typename pair_type::second_type & result_type; result_type operator()( pair_type &source ) const { return source.second; } }; I am compiling using BCB5 compiler in the IDE, should be equivalent to the free 5.5.1 command line compiler. While I could simply write a forwarding functor in a fraction of the time it will take me to solve this, there is definitely a ne tool I would like to add to my toolbox here once I understand what is happenning. Unfortunately I am getting somewhat lost in reference-to-reference issues, and the occasional compiler crash does not help. Any and all hints appreciated -- AlisdairM

1 0

Loki vs. Boost
by Hamlet 02 Oct '02

02 Oct '02

Hi, I'm (desperately) looking for a serious comparative review of Loki vs. Boost libraries. Although the differences are quite clear, still it would be nice to see a serious comparison, especially in the features that exists in both places, i.e. smart pointers, small obj. allocator, type traits and template meta-programming. Does anybody knows if there exists such a paper somewhere, or alternatively have his own insights about the libraries? Thanks, Ariel

2 1

[BGL] vertex_index_t w/VertexList=listS questions
by Chris Russell 02 Oct '02

02 Oct '02

Hi Jeremy, Using adjacency_list w/VertexList=listS, I've stuffed a vertex_index_t declaration into the internal vertex property map and got my DFS invocation to compile. Taking a look at the dijkstra-example-listS.cpp in the examples directory on CVS, I see how you manually initialize this property for each of the vertices after you build up the graph. p.230 of the book discusses the auto-update of the vertex_index_t property upon vertex removal for the case of VertexList=vecS but I'll need to affect this update myself for VertexList=listS? Also, can you foresee any problems if I register vertex_index_t with a value_type of long int instead of int? I'm guessing no because I'm passing it as a template parameter but I just want to make sure. - Thanks and regards Chris Russell

2 1

BOOST_PARAM_TEST_CASE and uncaught exceptions
by Alisdair Meredith 02 Oct '02

02 Oct '02

I have a case where my test case passed to BOOST_PARAM_TEST_CASE is throwing an exception I was not expecting. This seems to still result in the correct number of calls to the test case, but the first parameter in the list is passed every time. Is this a feature of my compiler, or an issue with the library? Using Borland C++ Builder 5 (should be same as free command-line compiler) -- AlisdairM

2 1

BUG: intrusive pointer and weak_ptr
by Petr Ferschmann 01 Oct '02

01 Oct '02

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, I think I found BUG. Let we have this program: - -- cut here -- #include <boost/shared_ptr.hpp> #include <boost/weak_ptr.hpp> #include <boost/intrusive_ptr.hpp> #include <cstdio> using namespace std; #define INTR class MujObjekt #ifdef INTR : public boost::counted_base #endif { public: MujObjekt() { printf( "MujObjekt::MujObjekt()\n" ); } void setThis( boost::shared_ptr<MujObjekt> obj ) { m_this = obj; } virtual ~MujObjekt() { printf( "MujObjekt::~MujObjekt()\n" ); } boost::weak_ptr<MujObjekt> m_this; }; int main() { boost::shared_ptr<MujObjekt> obj( new MujObjekt() ); obj->setThis( obj ); return( 0 ); } - --- cut here --- But in case of usage of intrusive pointer it doesn't call destructor - because there is weak pointer. But when I undefine INTR and it uses non-intrusive it works as expected. This is only modelling case to simulate bug. - -- Petr "Fers" Ferschmann -=[ petr(a)ferschmann.cz ]==[ http://petr.ferschmann.cz/ ]=- - -=[ Koukni na http://www.postcard.cz/ ]==[ +420 604/781 009 ]=- GPG Fingerprint: [83B0 6378 7A9D D993 035E 60BD FEEC F665 D2C8 1B9A] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.7 (GNU/Linux) iD8DBQE9mV9O/uz2ZdLIG5oRArF/AJ9LGfWTXfy69zNTsbiEKThTPQnWcwCeOWgj 0tX9AxdWJ8u/L1MkdZHjOPk= =7A3i -----END PGP SIGNATURE-----

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