March 2003 - Boost-users - lists.boost.org

boost::shared_ptr and stl algorithms
by Bill Eidson 15 Apr '05

15 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

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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

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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

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RE: [Boost-Users] How To Build Boost 1.30 With Dev-CPP?
by bjorn.karlsson＠readsoft.com 04 May '03

04 May '03

> From: firingme [mailto:yg-boost-users@m.gmane.org] > E:\LY\boost_1_30_0>bjam sTOOS=mingw This should read sTOOLS, not sTOOS. Bjorn

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Understanding MPL
by Edward Diener 18 Apr '03

18 Apr '03

I am trying to understand how the MPL library works. I first read "The Boost C++ Metaprogramming Library" by Aleksey Gurtovoy and David Abrahams. When I get to Basic Usage I see this: template< typename Condition , typename T1 , typename T2 > struct if_ { typedef /*unspecified*/ type; }; I am really having trouble understanding the next to last line. How can "typedef type;" be a valid C++ construct and, if it is, what does it mean ? I always though that a typedef must specify an actual type but I don't see any in the expression above.

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building boost with vc7
by oleg smolsky 03 Apr '03

03 Apr '03

Hello, I've just downloaded boost_1_30_0 and it turns out that there are two ways to build regex lib: bjam nmake /f vc7.mak However, they produce different libraries, and regex headers explicitly include ones generated by the makefile. e.g: boost_regex_vc7_mdi.lib boost_regex_vc7_mdid.lib ..... So, here are a few questions: -- why do above commands generate different libs? -- the nmake generates a full set of libs, but bjam does not, why? -- no other libs do have makefiles, why? Thanks in advance. Best regards, Oleg Smolsky Software Design Authority Allied Telesyn Research

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Problems building on Mac-OSX
by Roy Smith 03 Apr '03

03 Apr '03

I'm trying to build boost 1.30 on Mac OS-X 1.2.4. I'm using the compiler that came with the system, GCC-3.1. When I do "bjam -sTOOLS=darwin", I get a variety of errors and warnings. I get the warning "enumeration value `type_pf' not handled in switch", in several places in libs/regex/src/cregex.cpp. In all cases, the offending lines are protected by ifdefs: #ifndef BOOST_REGEX_NO_FILEITER case re_detail::RegExData::type_pf: return pdata->fm[i].matched; #endif It would appear that BOOST_REGEX_NO_FILEITER should be defined in the darwin environment, but isn't. This is the first time I've just Jam, so I'm at a loss to figure out why it's not set right, or how to fix it. More importantly, I get 6 failures. The bjam output contains the following for the first one: darwin-Link-DyLib-action libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime- link-static/shared-linkable-true/libboost_pr\ g_exec_monitor.dylib ld: Undefined symbols: cpp_main(int, char**) export DYLD_LIBRARY_PATH ld -dynamic -m -r -d -o "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/libboos\ t_prg_exec_monitor.lo" "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/execution_m\ onitor.o" "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/cpp_main.o" \ && \ c++ -static-libgcc -g -Wl,-dynamic -nostartfiles -Wl,-dylib -Wl,-ldylib1.o -Wl,-dylib_compatibility_version,1.30.0 -W,l-dylib_current_ver\ sion,1.30.0 -o "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/libboost_prg_exec_m\ onitor.dylib" "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/libboost_prg_exec_mo\ nitor.lo" \ \ \ && \ rm -f "libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime -link-static/shared-linkable-true/libboost_prg_exec_monitor\ .lo" ...failed darwin-Link-DyLib-action libs/test/build/bin/libboost_prg_exec_monitor.dylib/darwin/debug/runtime- link-static/shared-linkable-true/l\ ibboost_prg_exec_monitor.dylib... Unfortunately, I'm stumped.

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containers of boost::function objects
by Alisdair Meredith 02 Apr '03

02 Apr '03

I am trying to create a simple mechanism to register multiple callbacks with my class. My first simple-minded approach is to use std::list< boost::function2< [my params]> > Unfortunately, I cannot search this list to unregister callbacks, as any attempt to dereference a list::iterator tries to call the function, rather than return the function object. After spotting this problem in the standard algorithms I have been trying to hack around myself, explicitly calling operator* and even operator-> with no joy. Am I missing some easy way to get the function object out of the iterator as a value? And is this a bug in my compiler (BCB6) or a general issue for containers of function objects? -- AlisdairM

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regex++ use on binary data
by brian_hernacki 01 Apr '03

01 Apr '03

Maybe a newbiew question, but is there any way to use the regex++ libary to search chunks of binary data? (or more accurately to search a buffer of data of known length for a given pattern which may itself contain null bytes) --brian

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linking Signals Library
by John Fletcher 01 Apr '03

01 Apr '03

System: Red Hat 8.0 with gcc 3.2 Boost 1_30_0 I have built the boost signals library using bjam. The test suite runs and passes all tests. How do I make the resulting libraries available to my own programs? Is there an equivalent of 'make install' which will move the results to somewhere from which linking is possible? I have searched the documentation on Boost Signal and also on building libraries and have found nothing on this. Thanks John Fletcher

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