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[MultiArray] Bound Guarding
by loadcom 21 Dec '08

21 Dec '08

Hello, I'm using boost::multi_array for a while and find it very powerful except one point that I cannot specify an array_view's number of dimentions at runtime. But this pity is not the topic of this post. You know one can create an array_view with arbirary given start/bound indices as well as the stride as follows: typedef boost::multi_array<T, 3> array_t; array_t myarray; //... typedef array_t::index_range range_t; typename array_t::array_view::view<2> myview = myarrray[boost::indices[range_t(0, 8, 2)][rang_t()][1]]; As I don't know in the internal of the lib how the dound guarding of iteration is done, either - in the 'standard' STL manner as i!=bound; or - in the 'conventional' C stale as i<bound my concern is in case that one advetently specify 'range_t(0, 8, 2)' as range_t(0, 7, 2), if this error cause undefined behavior, or is as save as it correct form, or, seemingly impossible, detected at runtime or even compile time? Thanks for any concern. Best regards Max ------------------------------------------------------------------- 新浪空间——与朋友开心分享网络新生活！(http://space.sina.com.cn/ )

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Re: [Boost-users] [bind] Need Help - Function Composition
by loadcom 20 Dec '08

20 Dec '08

One step further, will the following version save one copy construction in make_less_by_func()? template <typename F> struct less_by_func { typedef bool result_type; const F & func_; less_by_func(const F & func) : func_(func) {} template<typename T> bool operator()(const T& lhs, const T& rhs) const { return func_(lhs) < func_(rhs); } }; // helper function template<typename F> less_by_func<F> make_less_by_func(const F& func) { return less_by_func<F>(func); } Thanks again. B/Rgds Max Hello Watanabe, Your code works well. And it's much more generic and elegant than the original version. Thank you so much! Best regards Max ------------------------------------------------------------------- 新浪空间——与朋友开心分享网络新生活！(http://space.sina.com.cn/ )

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[accumulators] Need help
by Neal Becker 20 Dec '08

20 Dec '08

I'm trying to define an accumulator for complex types, abs_sqr. The test program is attached. I get an error from gcc-4.3.2 which I've never seen, and is not informative: test_acc.cc:39: error: argument dependent lookup finds ‘struct boost::accumulators::tag::abs_sqr’ test_acc.cc:48: error: in call to ‘abs_sqr’

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[C++] Problems with undirected_dfs and color maps
by Zemmerie 20 Dec '08

20 Dec '08

I'm trying to use an undirected_dfs to find cycles in a graph. I have a visitor all ready to go, but I'm having trouble with the actual undirected_dfs() call. It wants me to give it a vertex color map and an edge color map, and I think that's where my problem is coming from. I managed to get something that will compile, but when it runs, it goes to the root node, then to one connected to it, then back to the root node, and just repeats. I think what's happening is that the color maps aren't working properly, so it doesn't know that the root node has already been discovered. Can anyone take a look at this and let me know what I'm doing wrong and how I can fix it? At this point I'm about ready to just write my own dfs algorithm! Thanks -Kate #include <boost/graph/adjacency_list.hpp> #include <boost/graph/graph_traits.hpp> #include <boost/graph/undirected_dfs.hpp> #include <boost/property_map.hpp> #include <boost/graph/graph_archetypes.hpp> #include <iostream> #include "CycleFinder.h" using namespace boost; using namespace std; //easier access to common types typedef boost::adjacency_list<vecS, vecS, undirectedS> Graph; typedef boost::graph_traits<Graph>::vertex_iterator vertex_iterator; typedef boost::graph_traits<Graph>::edge_iterator edge_iterator; typedef boost::graph_traits<Graph>::vertex_descriptor vertex_descriptor; typedef boost::graph_traits<Graph>::edge_descriptor edge_descriptor; int ConstraintsSolver::reduceClusterGraph(Graph cluster) { //search for 6-cycles and reduce them pair<vertex_iterator, vertex_iterator> vertexPair = vertices(cluster); vertex_descriptor rootNode = *vertexPair.first; CycleFinder finder; read_write_property_map_archetype<vertex_descriptor, default_color_type> vertexColorMap; read_write_property_map_archetype<edge_descriptor, default_color_type> edgeColorMap; undirected_dfs(cluster, finder, vertexColorMap, edgeColorMap, rootNode); return 0; } -- View this message in context: http://www.nabble.com/-C%2B%2B--Problems-with-undirected_dfs-and-color-maps… Sent from the Boost - Users mailing list archive at Nabble.com.

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Re: [Boost-users] [boost.build] should we not define _SECURE_SCL=0 by default for all msvc toolsets
by Thorsten Ottosen 20 Dec '08

20 Dec '08

Neil Groves skrev: > Thorsten, > > On Thu, Dec 4, 2008 at 3:05 PM, Thorsten Ottosen < > thorsten.ottosen(a)dezide.com> wrote: > >> Dear all, >> >> Is there are reason why we do not compile with this flag set by default? >> Are there any users of Boost out there which actually wants the securuty >> mode turned on? >> > > I personally prefer to have _SECURE_SCL=0 in Release builds too. For users > that also have to build against other libraries that are provided as > precompiled binaries that use the MSVC defaults this would break things. The > _SECURE_SCL setting changes the ABI. > > >> If not, then I suggest that we change the build settings. >> > > I think it would be ok to allow both options, but probably the default > should equal the Microsoft default with an easy way to opt-out of the > madness! But AFAIK, even the prebuilt binaries that you get from Boost Consulting are built with _SECURE_SCL=0. -Thorsten

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Need help with XCode - simple RegEx test app crashes on OS X (Darwin)
by Thomas Tempelmann 20 Dec '08

20 Dec '08

I wanted to try out boost for the first time and ran into a basic problem: The regex test app as suggested on the installation page crashes inside the destructor of "match_results". I wonder if the libs created by the boost installer are built in an incompatible manner to what XCode generates from my own test code. I could not find any troubleshooting or special instructions for using boost with XCode, though. Here's some more details: I've installed boost 1.37, on two Macs (both Intel, one with 10.5.5, other with 10.5.6), both XCode 3.1.2 (gcc 4.01). Once installed using the official distribution, using "configure" and "make install", once using MacPorts. Both build error-free, and similarly (only difference I could see is that the former installs in /usr/local/ while the other in /opt/local). I basically followed the unix install instructions from here: http://www.boost.org/doc/libs/1_37_0/more/getting_started/unix-variants.html #link-your-program-to-a-boost-library Chapter 6 then suggests to test a little regex program. I created a new C++ Tool project in XCode, put the test code into main.cpp and changed only these three build options: HEADER_SEARCH_PATHS = /opt/local/include LIBRARY_SEARCH_PATHS = /opt/local/lib OTHER_LDFLAGS = -lboost_regex-mt The app then builds fine without errors. And I can launch it, where it then waits for input. Meaning that boost basically works. It even performs the regex query just fine. Only then, when it loops around, it crashes with a segmentation fault deep inside the destructor of "boost::smatch matches". Here's the stack trace: Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x0000000067616c66 Crashed Thread: 0 Thread 0 Crashed: 0 libstdc++.6.dylib 0x92c57964 __gnu_debug::_Safe_iterator_base::_M_detach() + 62 1 libstdc++.6.dylib 0x92c579ce __gnu_debug::_Safe_iterator_base::_M_attach(__gnu_debug::_Safe_sequence_base *, bool) + 42 2 libstdc++.6.dylib 0x92c57ad4 __gnu_debug::_Safe_sequence_base::_M_detach_all() + 42 3 boost-test 0x00002c87 __gnu_debug::_Safe_sequence_base::~_Safe_sequence_base() + 23 4 boost-test 0x00002feb __gnu_debug::_Safe_sequence<__gnu_debug_def::vector<boost::sub_match<__gnu_c xx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > > >::~_Safe_sequence() + 23 5 boost-test 0x00003449 __gnu_debug_def::vector<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >::~vector() + 29 6 boost-test 0x000034db boost::match_results<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<boost::sub_match<__gnu_cxx::__normal_iterator<char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >::~match_results() + 23 7 boost-test 0x00002809 main + 215 (main.cpp:18) 8 boost-test 0x00002052 _start + 216 9 boost-test 0x00001f79 start + 41 Any ideas what's going wrong here?

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Re: [Boost-users] [boost] tweaking the review process
by David Abrahams 20 Dec '08

20 Dec '08

on Fri Dec 19 2008, Fabio Fracassi <f.fracassi-AT-gmx.net> wrote: > David Abrahams schrieb: >> on Wed Dec 17 2008, Fabio Fracassi <f.fracassi-AT-gmx.net> wrote: >> >>> David Abrahams schrieb: >>>> on Mon Dec 15 2008, John Phillips <phillips-AT-mps.ohio-state.edu> wrote: >>> [...] >>>>> I don't know if I was the first to do this, but I have done it. Looking at the >>>>> current contents of the instructions to review managers, either they have changed >>>>> since I started managing reviews or I somehow hallucinated extra words to add the >>> user >>>>> list to the lists that should receive an announcement of the review. >>>> An announcement is one thing; instructing people to post their reviews >>>> in the same list is a different thing entirely. >>>> >>> You don't have to, it happens almost automatically if you are not >>> careful. Many people write their Review as a reply to the original >>> announcement, and if you are not extra careful to remove the user list >>> from the recipients your review gets send to both lists. >> >> The poster of the announcement should make it clear how to post a >> review. I never liked the idea of reviews showing up in the list with >> the subject "Review period for Boost.XXXX begins today" anyway. Also >> s/he can set the Reply-To: field. >> > > When using thunderbird as a client to the gmane news gateway the Reply to fields don't > seem to work though. > I don't know if there is a technical solution to this particular > problem. I've never had a problem with Gnus' Reply-to functionality and gmane. It's hard to imagine that TBird is broken in this way. > Beside this I agree with you, if the original anouncement clearly states that reviews > and followups should go to .devel. > Still I think that sometimes some messages might go astray and maybe we should suggest > that the review manager and/or the submitter should have an eye on the users list, so > that nothing is lost. (and maybe forward those strays to .devel) Not a bad suggestion. -- Dave Abrahams BoostPro Computing http://www.boostpro.com

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Re: [Boost-users] [bind] code sample crashing MS compiler
by loadcom 20 Dec '08

20 Dec '08

In my understanding of boost::bind, your code has no problem. It's also accepted by my VS2003SP1 environment. B/Rgds Max ----- Original Message ----- From: Christian Henning To: boost-users(a)lists.boost.org Subject: [Boost-users] [bind] code sample crashing MS compiler Date: 2008-12-20 05:42:00 This following code sample will crash the MS compiler version 8. I hope there are some MS folks reading this mailing list, since I have no idea where else to post this. #include struct A { void operator() () { boost::bind( &A::lookup, *this, unsigned char() )(); } void lookup( unsigned char& c ) {} }; int main(int argc, char* argv[]) { A()(); return 0; } I know the code is not suppose to compile. Uncommenting the this pointer in the bind construct will make the code compile fine. Regards, Christian ------------------------------------------------------------------- 新浪空间——与朋友开心分享网络新生活！(http://space.sina.com.cn/ )

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error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'const is a user-defined type, however, I'm getting the following:'
by Joseph A. Marks 20 Dec '08

20 Dec '08

Has anyone seen an error like this? SpecialDate is a user-defined type, however, I'm getting the following: boost/test/test_tools.hpp(326) : error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'const is a user-defined type, however, I'm getting the following: ' (or there is no acceptable conversion) Thanks in Advance, Joseph A. Marks e-mail: josephamarks(a)yahoo.com

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Re: [Boost-users] [C++] Boost::Regex beginner question
by Alan M. Carroll 20 Dec '08

20 Dec '08

I don't know if I can help you with that. A few things to consider 1) Why do you use boost::regex but regex_replace? I would try boost::regex_replace and see if that makes a difference. 2) The boost::regex_replace function is not in the boost/regex.hpp header, it's in another file (regex_replace.hpp) in a subdirectory which is included by regex.hpp. I would verify that you have a header with that function in it. 3) You could try downloading the Boost library and see if the code compiles. Regex requires a library but if does compile you know your current headers are broken in some way. 4) I would see what happens if you don't include windows.h. Every time I have included that and any STL/Boost headers I have had problems, so I no longer use windows.h in any real source file, only in simple glue logic ones. windows.h is an almost perfect storm of incompatibility and bad practice. At 09:44 AM 12/19/2008, P.C. wrote: >thank you for the response. unfortunately, we've tried to use the >regex_replace function, but it gave an unexpected error: >'regex_replace' : undeclared identifier >we used it in the following way: >NOTE: the Regex++ we are using was downloaded from the original >author's site, not entirely with the Boost library. we can't >understand this error. if we downloaded and installed it according to >the installation instructions for VC++, how can a function be missing?

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