March 2005 - Boost-users - lists.preview.boost.org

boost::iterator_facade problem with postfix increment proxy
by Jens Theisen 24 Mar '05

24 Mar '05

I want to implement my own iterator as single pass traversal with reference type value& (a genuine reference). My problem is, that the iterator facade concludes from the single pass traversal, that this is an input/output iterator and those are generelly subject to a postfix increment proxy. That is, writing *iter++ = some_value; doesn't really do anything but changing a temporary value in the proxy. In addition to this, iter++ == iter would't find a suited overload, which seems to be a bug. Chancing the traversal tag to forward traversal works correct, but that's not really what I want to do. I want my iterator to be single pass since I don't support the i == j => ++i == ++j requirement. Jens

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[Boost.Test] (Solution) for Visual Studio - Link error, need to be pointed in the right direction
by Peter 24 Mar '05

24 Mar '05

Gennadiy, Once again thanks for the help. Since I could not find anything clear on how to do this myself I thought I would share it with the list and anyone else who does not know how to do this. This process allows me to create a fresh Visual 2005 C++ project and compile the various Boost.Test Unit Testing Framework examples, located under the boost.test documentation branch on the boost website. Assumptions: You have correctly installed and setup Boost (see http://www.boost.org/more/getting_started.html for more information). _Step 1_ File -> New -> Project -> General -> Console (within the wizard choose empty project and console application) _Step 2_ Create a New C++ source code file (*.cpp), add the example code you wish to run _Step 3_ Bring up the properties for the project (Within Solution Explorer right click and select properties on the project) Expand the C/C++ node of the treeview: * Select preprocessor and within the Preprocessor Definitions add the "BOOST_TEST_NO_AUTO_LINK" directive. * Select Code Generation and change the Runtime Library to "Multi-threaded Debug DLL (/MDd)" Expand the Linker node of the treeview: * Select Input and within the Additional Dependencies add "libboost_unit_test_framework-vc80-mt-gd.lib" _Step 4_ Save the project properties. _Step 5_ Compile the code. Notes: 1. The actual Lib file (libboost_unit_test_framework-vc80-mt-gd.lib) may be different for each system? Also I am guessing the Release version to link against will be the lib file without the gd. Also I think the runtime library setting will change to. 2. I have not figured out how to get the output of the tests to appear within the IDE. Currently I do a dodgy and just put a breakpoint within unit_test_main.cpp. Yes I know this is dodgy but I am still learning my way. I hope this helps others interested in using boost and specifically the Unit Test Framework within boost. (I know I would have a week ago :p) Peter.

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regex_search (extended syntax) can search to the end of the iterator
by David McKelvie 23 Mar '05

23 Mar '05

>> It seems that regex_search iterates to the end of the sequence >> using ++iterator rather than stopping once it has found the first match John Maddock replied: >> 1) reproduce the behaviour with 1.32. >> 2) Let me have a reproducible test case. >> 3) Check that it's not a call to std::distance that seeking the iterator to >> the end (it shouldn't be). I have now reproduced the behaviour with Boost 1.32. I include a test case below. It does seem to be a call to std::distance which is seeking the end. The problem arises only if boost::regex::extended is specified at break /usr/local/include/boost-1_32/boost/regex/v4/perl_matcher_common.hpp:418 m_result.maybe_assign(*m_presult) is being called which then calls std::distance which does the seek to the end. The problem is probably in my iterator implementation as this is the first Ive tried to write, But that seems simple enough, so maybe its more general. This is running on Linux Fedora Core 1 Boost 1.32 gcc version 3.3.2 20031022 (Red Hat Linux 3.3.2-1) David

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[BGL] Question about push_relabel_max_flow
by Matthias Linkenheil 23 Mar '05

23 Mar '05

Hello, I used the edmunds_karp_max_flow algorithm in my project and it worked fine. Then I changed it to the push_relabel_max_flow algorithm but it doesn't work. I get an access violation at line 562 in the push_relabel_max_flow.hpp . Have anyone an idea where the problem could be? Line 558 - line 565 of push_relabel_max_flow.hpp : // do the bottom u = bos; ai = out_edges(u, g).first; while (excess_flow[u] > 0) { if (capacity[*ai] == 0 && is_residual_edge(*ai)) push_flow(*ai); ++ai; } Thanks, Matthias

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BGL: a quick question on bundled properties and graph traits
by Elvanör 23 Mar '05

23 Mar '05

Hello, How can I get the type of my vertex properties if I use bundled properties as internal properties? My example is this one: typedef adjacency_list<mapS, vecS, undirectedS, myClass> Graph; // and in one function: template <class graph> void myFunction (Graph & g) { // Here I need to declare an object of type myClass... how can I get this type using graph_traits ?? } Thanks. Again, the documentation on bundled properties really need to be improved, IMHO. All the information I could find was relevant to the old property maps mechanism... Jean-Noël

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copy_file reliable?
by Oliver Kowalke 23 Mar '05

23 Mar '05

Hello, is boost::filesystem::copy_file reliable? If the os indicates some failure during copy of a file (for instance no more space available) the destination file is removed or left in an incomplete state? thx, Oliver -- "Happy ProMail" bis 24. M�rz: http://www.gmx.net/de/go/promail Zum 6. Geburtstag gibt's GMX ProMail jetzt 66 Tage kostenlos!

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Why does regex_search search to the end of the iterator?
by David McKelvie 23 Mar '05

23 Mar '05

Could anyone explain the following behaviour of regex_search (In /usr/include/boost/regex/v3/regex_match.hpp, so Version 3) Using regex_search acting on a pair of iterators, with input "aaa bbb ccc\naaaaaaX" and regexp "(aaa)|(bbb)|(.)|(\n)" and the match_continuous flag set. It seems that regex_search iterates to the end of the sequence using ++iterator rather than stopping once it has found the first match or even the longest match. Why is this? I guess it is an optimisation to speed up subsequent matches. Is there a way of avoiding this? I have an application in mind where maybe I dont have the entire sequence or rather I'd like the match before I have the complete sequence. thanks, David --- details -- Why does regex_search iterate to the end of the sequence in the following situation, with match_continuous set It seems to me that it could stop as soon as it finds 'aaa' and not iterate further. expression.assign("(aaa)|(bbb)|(.)|(\n)"); // Regular expression const char * input = "aaa bbb ccc\naaaaaaX"; // Input string MyCharIter start = my_begin(input), end = my_end(input); boost::match_results<MyCharIter> what; boost::regex::flag_type flags = boost::match_default | boost::match_not_dot_newline | boost::match_continuous ; regex_search(start,end, what, expression, flags); MyCharIter is just a test iterator on the string with MyCharIter& MyCharIter::operator++(){ // prefix ++X printf("NT: ++X called bp=%d c= '%c'\n",bp,s[bp]); ++bp; return *this; } The output is NT: ++X called bp=0 c= 'a' NT: ++X called bp=1 c= 'a' NT: ++X called bp=2 c= 'a' NT: ++X called bp=0 c= 'a' NT: ++X called bp=1 c= 'a' NT: ++X called bp=2 c= 'a' NT: ++X called bp=3 c= ' ' NT: ++X called bp=4 c= 'b' NT: ++X called bp=5 c= 'b' NT: ++X called bp=6 c= 'b' NT: ++X called bp=7 c= ' ' NT: ++X called bp=8 c= 'c' NT: ++X called bp=9 c= 'c' NT: ++X called bp=10 c= 'c' NT: ++X called bp=11 c= ' ' NT: ++X called bp=12 c= 'a' NT: ++X called bp=13 c= 'a' NT: ++X called bp=14 c= 'a' NT: ++X called bp=15 c= 'a' NT: ++X called bp=16 c= 'a' NT: ++X called bp=17 c= 'a' NT: ++X called bp=18 c= 'X' NT: ++X called bp=0 c= 'a' NT: ++X called bp=0 c= 'a' NT: ++X called bp=1 c= 'a' NT: ++X called bp=2 c= 'a' NT: ++X called bp=0 c= 'a' NT: ++X called bp=0 c= 'a' NT: ++X called bp=1 c= 'a' NT: ++X called bp=2 c= 'a' NT: ++X called bp=0 c= 'a' NT: ++X called bp=1 c= 'a' NT: ++X called bp=2 c= 'a' ******** N = 0 Result = aaa

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compiling error using Boost with VC++ 6
by Samvit Prakash 23 Mar '05

23 Mar '05

Hi, First a confession: I am new to VC++ AND to BOOST...I thought the best way to learn both was to dive right in...and now I'm looking for a life-guard! OK, so here's the problem: I have installed the Boost Library in its default location (C:/Boost... ). When I try to compile the code random_demo.cpp (link to the code: http://www.boost.org/libs/random/random_demo.cpp) I get the following error: "fatal error C1083: Cannot open include file: 'boost/random/linear_congruential.hpp': No such file or directory Error executing cl.exe." Clicking on the error leads me to the following source of error in the code: #include <boost/random/linear_congruential.hpp> I have added the root Boost directory to the directory path: (tools>options>directories > I added C:\Boost there for "include files") So I am not sure why the compiler can't locate the file. Any help would be appreciated. Thanks, samvit

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Using Boost after installation
by Ioannis Vranos 23 Mar '05

23 Mar '05

I installed Boost 1.32 to VS 2003 and MINGW 3.4.2 (got 80 failures for the second), and now I am trying to use it with both but the compiler's can't find the boost header files by their own. For example the source code: #include <boost/static_assert.hpp> int main() { int i=1; BOOST_STATIC_ASSERT(i==1); } produces: C:\c>g++ temp.cpp -o temp.exe temp.cpp:1:35: boost/static_assert.hpp: No such file or directory temp.cpp: In function `int main()': temp.cpp:7: error: `BOOST_STATIC_ASSERT' undeclared (first use this function) temp.cpp:7: error: (Each undeclared identifier is reported only once for each fu nction it appears in.) C:\c>cl /EHsc temp.cpp Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.10.3077 for 80x86 Copyright (C) Microsoft Corporation 1984-2002. All rights reserved. temp.cpp temp.cpp(1) : fatal error C1083: Cannot open include file: 'boost/static_assert. hpp': No such file or directory C:\c> I tried everything I could think like adding the c:\Boost folder and subfolders in PATH environment variable, or explicitly #include the file with its entire path, with no result. What am I missing here? Thanks in advance.

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Re: [Boost-users] [Boost.Test] Link error, need to be pointed in the right direction
by Peter 23 Mar '05

23 Mar '05

Hi Gennadiy, Thanks for replying. Comments following. > * To: boost-users@xxxxxxxxxxxxxxx <mailto:boost-users@DOMAIN.HIDDEN> > * Subject: [Boost-users] Re: [Boost.Test] Link error,need to be pointed in the right direction > * From: "Gennadiy Rozental" <gennadiy.rozental@xxxxxxxxxxx <mailto:gennadiy.rozental@DOMAIN.HIDDEN> > > * Date: Sun, 20 Mar 2005 23:50:50 -0500 > * Organization: Thomson Financial > * References: <A3FB6A3DCF268B47A774EA32AE996CC338E3(a)quantum.Billswan.local <http://lists.boost.org/MailArchives/boost-users/msg10496.php> > > * Reply-to: boost-users@xxxxxxxxxxxxxxx <mailto:boost-users@DOMAIN.HIDDEN> > * Sender: news <news@xxxxxxxxxxxxx <mailto:news@DOMAIN.HIDDEN> > > > ________________________________ > > You need to link with the Unit Test Framework component of Boost.Test > > Compile it (using bjam or you could use project file supplied with library, > VC 2005 will cmvert it to appropriate format automatically) and add to the > list of libraries to link with. > > HTH, > > Gennadiy I knew I had to link it against the Unit Test Framework libraries I just wasn't sure exactly where to stipulate this. I didn't realise that you had included some VC project files as an initial starting point. Anyway I still need some help, I am almost there now .... I can feel it :p. This is what I have done. I have opened up the Version 7.1 project file(s), taking one at random ..\boost_1_32_0\libs\test\build\msvc71_proj\unit_test_example2.vcproj I converted this file to the new format. Looking through all the project settings I found a number of items that you set (or whoever initially setup the projects). The most interesting (disturbing) appears to be where you specify the lib file dependency which is set to "unit_test_framework.lib", looking through the (bjam) compiled lib directory I cannot find a lib file with that name the closest files I have are: ------------------------ D:\Development\boost\lib\dir *unit_test* Volume in drive D is Applications Volume Serial Number is A8BC-D142 Directory of D:\Development\boost\lib 03/03/2005 09:04 PM 1,385,358 libboost_unit_test_framework-vc80-mt-1_32.lib 03/03/2005 09:04 PM 6,076,308 libboost_unit_test_framework-vc80-mt-gd-1_32.lib 03/03/2005 09:04 PM 6,076,308 libboost_unit_test_framework-vc80-mt-gd.lib 03/03/2005 09:04 PM 1,936,966 libboost_unit_test_framework-vc80-mt-s-1_32.lib 03/03/2005 09:04 PM 1,936,966 libboost_unit_test_framework-vc80-mt-s.lib 03/03/2005 09:04 PM 6,957,836 libboost_unit_test_framework-vc80-mt-sgd-1_32.lib 03/03/2005 09:04 PM 6,957,836 libboost_unit_test_framework-vc80-mt-sgd.lib 03/03/2005 09:04 PM 1,385,358 libboost_unit_test_framework-vc80-mt.lib 03/03/2005 09:04 PM 1,936,678 libboost_unit_test_framework-vc80-s-1_32.lib 03/03/2005 09:04 PM 1,936,678 libboost_unit_test_framework-vc80-s.lib 03/03/2005 09:04 PM 4,495,796 libboost_unit_test_framework-vc80-sgd-1_32.lib 03/03/2005 09:04 PM 4,495,796 libboost_unit_test_framework-vc80-sgd.lib 12 File(s) 45,577,884 bytes 0 Dir(s) 297,679,298,560 bytes free ------------------------ Now I am guess I need to change that lib file to one of these. Going through the project settings I have Multi-Threading on and it is obviously in debug mode. Looking at the bottom of this page: http://www.boost.org/more/getting_started.html it describes what each of the parts of the file name means (so I need mt, g and d). Based on this information I chose: libboost_unit_test_framework-vc80-mt-gd.lib This appears to work. Is this correct? Or have a managed to add 2 + 2 and get 5? As a slight aside the IDE does not display the output of the Unit test. Was it supposed to? I was under the impression that it should have. One minor think that I think I found. Looking within the jamfile ..\boost_1_32_0\libs\test\build\Jamfile. I think that it is saying that it needs a lib file named boost_unit_test_framework. I don't know if this is or isnt the case (I have never used bjam before compiling boost), I just thought I would mention it just in case that it is wrong as well. Enough rambling from me now. Thanks for reading through this and I appreciate any help anyone can provide. Peter.

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