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[graph] hash_setS
by liquid 20 Apr '09

20 Apr '09

How to use hash_setS in adjacent_list? If I define BOOST_HAS_HASH the compiler will generate "error C2977: 'stdext::hash_set' : too many template arguments". This is caused by using "BOOST_STD_EXTENSION_NAMESPACE::hash_set<Key,Eq,Hash,Alloc>" in definition of "template <class Key, class Eq, class Hash, class Alloc> struct container_traits< BOOST_STD_EXTENSION_NAMESPACE::hash_set<Key,Eq,Hash,Alloc> > { typedef set_tag category; typedef stable_tag iterator_stability; // is this right? };" Class hash_set is defined in STL as follows: template<class _Kty, class _Tr = hash_compare<_Kty, _STD less<_Kty> >, class _Alloc = _STD allocator<_Kty> > class hash_set : public _Hash<_Hset_traits<_Kty, _Tr, _Alloc, false> > {...}; which has only 3 params. I'm using VS2008 Regards liquid

2 1

How to perform the VeecoFTC test, Thanks:)
by francisleetang 20 Apr '09

20 Apr '09

Hi, all, I am a new guy to Boost. I try to perform the regression test on WINCE and I found the VeecoFTC on http://www.boost.org/development/tests/trunk/developer/summary.html. But after 3 days' try and google the message about this test, I cannot perform the test on my machine. Can anybody help me? Thanks! Note: I change the msvc9.0 in VeecoFTC to msvc8.0 because I only installed the msvc8.0 on my machine. The information below is how I perform the test. 1. run on the command line: python run.py --runner=VeecoFTC --timeout=30 --user=anonymous --incremental --bjam-toolset=vc8 --pjl-toolset=msvc --toolsets=msvc/toolset-msvc:version=8.0~wm5~stlport5.2/stdlib=stlport-5.2~evc8~arm,msvc/toolset-msvc:version=8.0~stlport5.2/stdlib=stlport-5.2~vc8 The test failed 2. Add the user-config.jam part found in VeecoFTC page to C:\VeecoFTC\boost\tools\build\v2\user-config.jam 3. Follow the user-config.jam, I make a directory C:\VeecoFTC\boost\TestTools, and found the "WM5TestLauncher" source code, build it and placed it to C:\VeecoFTC\boost\TestTools. 4. Found the VSVars32-VC8-WM5.bat on web and placed it to C:\VeecoFTC\boost\TestTools. 5. run command in step 1 with option "--have-source" again. The test still failed with the messages below: # Making "C:\VeecoFTC\results" directory... # Starting tests ("C:\VeecoFTC\tools_bjam\bin.ntx86\bjam.exe" "-sBOOST_BUILD_PATH=C:\VeecoFTC;C:\VeecoFTC\tools_bb" "- OOST_ROOT=C:\VeecoFTC\boost" "--boost=C:\VeecoFTC\boost" "--boost-build=C:\VeecoFTC\tools_bb" "--debug-configuration" l1800 msvc/toolset-msvc:version=8.0~wm5~stlport5.2/stdlib=stlport-5.2~evc8~arm msvc/toolset-msvc:version=8.0~stlport5. stdlib=stlport-5.2~vc8 -d2 preserve-test-targets=off --dump-tests "--build-dir=C:\VeecoFTC\results" >>"C:\VeecoFTC\re lts\bjam.log" 2>&1)... C:\VeecoFTC\boost\status>"C:\VeecoFTC\tools_bjam\bin.ntx86\bjam.exe" "-sBOOST_BUILD_PATH=C:\VeecoFTC;C:\VeecoFTC\tools b" "-sBOOST_ROOT=C:\VeecoFTC\boost" "--boost=C:\VeecoFTC\boost" "--boost-build=C:\VeecoFTC\tools_bb" "--debug-configur ion" -l1800 msvc/toolset-msvc:version=8.0~wm5~stlport5.2/stdlib=stlport-5.2~evc8~arm msvc/toolset-msvc:version=8.0~st ort5.2/stdlib=stlport-5.2~vc8 -d2 preserve-test-targets=off --dump-tests "--build-dir=C:\VeecoFTC\results" 1>>"C:\Ve oFTC\results\bjam.log" 2>&1 # Running Boost.Build tests Traceback (most recent call last): File "C:\VeecoFTC\run.py", line 60, in <module> runner(root) File "C:\VeecoFTC\tools_regression_src\regression.py", line 193, in __init__ self.main() File "C:\VeecoFTC\tools_regression_src\regression.py", line 551, in main getattr(self,action_m)() File "C:\VeecoFTC\tools_regression_src\regression.py", line 516, in command_regression self.command_test() File "C:\VeecoFTC\tools_regression_src\regression.py", line 317, in command_test self.command_test_boost_build() File "C:\VeecoFTC\tools_regression_src\regression.py", line 354, in command_test_boost_build "boost/bin.v2/libs/any/test/any_test.test")); WindowsError: [Error 3] The system cannot find the path specified: 'C:\\VeecoFTC\\results\\boost/bin.v2/libs/any/test/ y_test.test/*.*' The attachments are the key configure files and error logs on my machine. Best Regards, Francis

1 0

BGL:add vertex and edge to subgraph
by Alice.gugu 20 Apr '09

20 Apr '09

Hi, I want to generate a local spanning tree of one graph(not MST) so I construct a subgraph of the original graph by add_vertex() and add_edge() function. The problem is that after the add_vertex(). the local tree generate edges between the vertexes automaticlly. If I call add_edge() again, it will dumplicat edges since all the edges between existing vertex have been added by add_vertex() function. I checked the example code of how to add vertex and edge in subgraph. It seems the add_vertex() function should not add edges automaticlly. SUBGRAPH m_g; ... //Create spanning tree SUBGRAPH& localTree = m_g.create_subgraph(); //Add one vertex as root in spanning tree boost::add_vertex(m_root, localTree); //Add descendants to the tree typedef graph_traits<SUBGRAPH> GTraits; GTraits::out_edge_iterator tmpei, tmpei_end; std::pair<GTraits::out_edge_iterator, GTraits::out_edge_iterator> p; p = out_edges(m_root, m_g); tmpei = p.first; tmpei_end = p.second; while ( tmpei != tmpei_end ) { //Descendant PolyGraphVertex tmpv = target(*tmpei , m_g); //Add descendant boost::add_vertex(tmpv, localTree); //Add an edge from ancestor to descendant boost::add_edge(m_root,tmpv,localTree); tmpei++; }

1 0

Boost python refuses to compile on OSX
by Pim Schellart 19 Apr '09

19 Apr '09

Dear Users/Developers, I followed the instructions on http://www.boost.org/doc/libs/1_38_0/libs/python/doc/building.html to install and build the boost python library. When running the command bjam toolset=gcc --verbose-test test from the /usr/local/boost_1_38_0/libs/python/example/quickstart directory I get the following output (a bit long I know :)): ...patience... ...patience... ...found 1356 targets... ...updating 54 targets... common.mkdir bin common.mkdir bin/test_ext.test common.mkdir bin/test_ext.test/gcc-4.0.1 common.mkdir bin/test_ext.test/gcc-4.0.1/debug common.mkdir bin/gcc-4.0.1 common.mkdir bin/gcc-4.0.1/debug gcc.compile.c++ bin/gcc-4.0.1/debug/extending.o common.mkdir ../../../../bin.v2 common.mkdir ../../../../bin.v2/libs common.mkdir ../../../../bin.v2/libs/python common.mkdir ../../../../bin.v2/libs/python/build common.mkdir ../../../../bin.v2/libs/python/build/gcc-4.0.1 common.mkdir ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ numeric.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ list.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ long.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ dict.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ tuple.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ str.o ../../../../libs/python/src/str.cpp: In function ‘boost::python::ssize_t boost::python::detail::<unnamed>::str_size_as_py_ssize_t(size_t)’: ../../../../libs/python/src/str.cpp:29: warning: comparison between signed and unsigned integer expressions gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ slice.o common.mkdir ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/from_python.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/registry.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/type_id.o common.mkdir ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/object gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/enum.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/class.o ../../../../libs/python/src/object/class.cpp: In function ‘boost::python::api::object boost::python::objects::<unnamed>::new_class(const char*, size_t, const boost::python::type_info*, const char*)’: ../../../../libs/python/src/object/class.cpp:510: warning: comparison between signed and unsigned integer expressions gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/function.o ../../../../libs/python/src/object/function.cpp: In member function ‘PyObject* boost::python::objects::function::call(PyObject*, PyObject*) const’: ../../../../libs/python/src/object/function.cpp:169: warning: comparison between signed and unsigned integer expressions gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/inheritance.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/life_support.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/pickle_support.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ errors.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ module.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/builtin_converters.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/arg_to_python_base.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/iterator.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/stl_iterator.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object_protocol.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object_operators.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ wrapper.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ import.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ exec.o gcc.compile.c++ ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object/function_doc_signature.o gcc.link.dll ../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ libboost_python-gcc40-d-1_38.dylib ld: unknown option: -R collect2: ld returned 1 exit status "g++" -L"/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib" -L"/Applications/scisoft/i386/ Packages/Python-2.5.2/Python.framework/Versions/2.5/lib/python2.5/ config" -Wl,-R -Wl,"/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib" -Wl,-R -Wl,"/Applications/scisoft/ i386/Packages/Python-2.5.2/Python.framework/Versions/2.5/lib/python2.5/ config" -o "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ libboost_python-gcc40-d-1_38.dylib" -Wl,-h -Wl,libboost_python-gcc40- d-1_38.dylib -shared -Wl,--start-group "../../../../bin.v2/libs/python/ build/gcc-4.0.1/debug/numeric.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/list.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/long.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/dict.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/tuple.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/str.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/ debug/slice.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/from_python.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/converter/registry.o" "../../../../bin.v2/libs/python/ build/gcc-4.0.1/debug/converter/type_id.o" "../../../../bin.v2/libs/ python/build/gcc-4.0.1/debug/object/enum.o" "../../../../bin.v2/libs/ python/build/gcc-4.0.1/debug/object/class.o" "../../../../bin.v2/libs/ python/build/gcc-4.0.1/debug/object/function.o" "../../../../bin.v2/ libs/python/build/gcc-4.0.1/debug/object/inheritance.o" "../../../../ bin.v2/libs/python/build/gcc-4.0.1/debug/object/life_support.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/object/ pickle_support.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/ debug/errors.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ module.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ converter/builtin_converters.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/converter/arg_to_python_base.o" "../../../../bin.v2/ libs/python/build/gcc-4.0.1/debug/object/iterator.o" "../../../../ bin.v2/libs/python/build/gcc-4.0.1/debug/object/stl_iterator.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/debug/ object_protocol.o" "../../../../bin.v2/libs/python/build/gcc-4.0.1/ debug/object_operators.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/wrapper.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/import.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/exec.o" "../../../../bin.v2/libs/python/build/ gcc-4.0.1/debug/object/function_doc_signature.o" -Wl,-Bstatic -Wl,- Bdynamic -lpython2.5 -Wl,--end-group -g ...failed gcc.link.dll ../../../../bin.v2/libs/python/build/gcc-4.0.1/ debug/libboost_python-gcc40-d-1_38.dylib... ...skipped <pbin/gcc-4.0.1/debug>extending.so for lack of <p../../../../bin.v2/libs/python/build/gcc-4.0.1/debug>libboost_python- gcc40-d-1_38.dylib... ...skipped <pbin/test_ext.test/gcc-4.0.1/debug>test_ext for lack of <pbin/gcc-4.0.1/debug>extending.so... common.mkdir bin/test_embed.test common.mkdir bin/test_embed.test/gcc-4.0.1 common.mkdir bin/test_embed.test/gcc-4.0.1/debug gcc.compile.c++ bin/gcc-4.0.1/debug/embedding.o ...skipped <pbin/gcc-4.0.1/debug>embedding for lack of <p../../../../ bin.v2/libs/python/build/gcc-4.0.1/debug>libboost_python-gcc40- d-1_38.dylib... ...skipped <pbin/test_embed.test/gcc-4.0.1/debug>test_embed.run for lack of <pbin/gcc-4.0.1/debug>embedding... ...failed updating 1 target... ...skipped 6 targets... ...updated 47 targets... The test does not run automatically but if I try to run it manually I get: python test_extending.py Trying: from extending import * Expecting nothing ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 6, in test_extending Failed example: from extending import * Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[0]>", line 1, in <module> from extending import * ImportError: No module named extending Trying: hi = hello('California') Expecting nothing ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 7, in test_extending Failed example: hi = hello('California') Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[1]>", line 1, in <module> hi = hello('California') NameError: name 'hello' is not defined Trying: hi.greet() Expecting: 'Hello from California' ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 8, in test_extending Failed example: hi.greet() Exception raised: Traceback (most recent call last): File "/ Applications/scisoft/i386/Packages/Python-2.5.2/Python.framework/ Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[2]>", line 1, in <module> hi.greet() NameError: name 'hi' is not defined Trying: invite(hi) Expecting: 'Hello from California! Please come soon!' ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 10, in test_extending Failed example: invite(hi) Exception raised: Traceback (most recent call last): File "/ Applications/scisoft/i386/Packages/Python-2.5.2/Python.framework/ Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[3]>", line 1, in <module> invite(hi) NameError: name 'invite' is not defined Trying: hi.invite() Expecting: 'Hello from California! Please come soon!' ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 12, in test_extending Failed example: hi.invite() Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/Python.framework/ Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[4]>", line 1, in <module> hi.invite() NameError: name 'hi' is not defined Trying: class wordy(hello): def greet(self): return hello.greet(self) + ', where the weather is fine' Expecting nothing ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 15, in test_extending Failed example: class wordy(hello): def greet(self): return hello.greet(self) + ', where the weather is fine' Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[5]>", line 1, in <module> class wordy(hello): NameError: name 'hello' is not defined Trying: hi2 = wordy('Florida') Expecting nothing ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 19, in test_extending Failed example: hi2 = wordy('Florida') Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/ Python.framework/Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[6]>", line 1, in <module> hi2 = wordy('Florida') NameError: name 'wordy' is not defined Trying: hi2.greet() Expecting: 'Hello from Florida, where the weather is fine' ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 20, in test_extending Failed example: hi2.greet() Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/Python.framework/ Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[7]>", line 1, in <module> hi2.greet() NameError: name 'hi2' is not defined Trying: invite(hi2) Expecting: 'Hello from Florida! Please come soon!' ********************************************************************** File "/usr/local/boost_1_38_0/libs/python/example/quickstart/ test_extending.py", line 22, in test_extending Failed example: invite(hi2) Exception raised: Traceback (most recent call last): File "/Applications/scisoft/i386/Packages/Python-2.5.2/Python.framework/ Versions/2.5/lib/python2.5/doctest.py", line 1228, in __run compileflags, 1) in test.globs File "<doctest test_extending[8]>", line 1, in <module> invite(hi2) NameError: name 'invite' is not defined 1 items had no tests: test_extending.run ********************************************************************** 1 items had failures: 9 of 9 in test_extending 9 tests in 2 items. 0 passed and 9 failed. ***Test Failed*** 9 failures. Does anyone have any idea what is going wrong? Kind regards, Pim Schellart

2 1

MPI auto-detection failed: unknown wrapper compiler mpic++
by wuguangjun 19 Apr '09

19 Apr '09

Hello boost-users, I install boost_1-38 in centOS5.3. with following command; ./configure -with-libraries=all Then I add "using mpi ;" into user-configure.jam, when I make the MakeFile ,an error occur, ./tools/jam/src/bin.linuxx86/bjam --user-config=user-config.jam MPI auto-detection failed: unknown wrapper compiler mpic++ Please report this error to the Boost mailing list: http://www.boost.org You will need to manually configure MPI support. warning: Graph library does not contain optional GraphML reader. note: to enable GraphML support, set EXPAT_INCLUDE and EXPAT_LIBPATH to the note: directories containing the Expat headers and libraries, respectively. warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. Building Boost.Regex with the optional Unicode/ICU support disabled. Note: Please refer to the Boost.Regex documentation for more information Note: this is a strictly optional feature. Is there something wrong? 2009-04-17 wuguangjun

3 3

multi-type containers
by László Marák 19 Apr '09

19 Apr '09

Dear Boost Users, I am getting started with boost.python. I want to port an image processing library into python. My problem is, that I have several pixel types (like int, float, etc.) which I'd love to handle in the same object by downcasting. In c++ it's something like this: class image {}; class float_image : image { float * pixels; // or boost::array_ptr<float> } class int_image : image { int * pixels; // or boost::array_ptr<int> } I can create the image object by: image * A = new float_image() image * B = new int_image() Now I'd have a virtual functions virtual float image::get_element() virtual int image::get_element() obviously this won't pass in c++, but in python it should pose no difficulty, as python uses dynamic casting. Is there a manner to do this with c++/boost/python? thank you for considering, Laszlo

2 1

installing Windows x64
by John Dlugosz 19 Apr '09

19 Apr '09

The boost-pro installer for Windows didn't download any x64 versions. Is there a different way to get that? TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

2 1

[interprocess]message_queue in Windows service
by Laurence Chambenois 18 Apr '09

18 Apr '09

Hi, I write a Windows Service that answer to requests through a message_queue. The message queue is created by the service, and then by the user starting the service (local system account). When another application, launched by another user, wants to connect to the message queue, it cannot. Because the mapped file is not in the same temporary directory. My question is : how can I do to create a message queue that can be accessed by any user ? Thanks for your help

2 1

Converting an existing thread to use boost.thread
by Sean Farrow 18 Apr '09

18 Apr '09

Hi; I am in the process of converting an existing thread function originally called using BeginThread to use boost.thread. I have a coupple of questions: 1. How would I go about returning to the existing thread, I use windows event handles and when one is signaled the thread ends, can I still use a while loop to do this, such as: Do { Code While(returnFromThread !=true); 2. Does boost::thread allow me the create mutex's and does it inherit windows mutex handles. 3. Can I tell a thread to run as soon as it starts or do I have to use the call boost.join. Any help apreciated. Cheers San. __________ Information from ESET NOD32 Antivirus, version of virus signature database 4018 (20090418) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

1 0

Exposing std::pair to Python
by A B 18 Apr '09

18 Apr '09

Hi, I am wondering if anyone has a working example of exposing std::pair as a Python tuple or list. Technically, I need to expose a vector of tuples and the following works class_<std::vector<std::pair<std::string, double> > >("VectorPair") .def(vector_indexing_suite<std::vector<std::pair<std::string, double> > >()) ; but I am not sure how then to expose the std::pair. I am guessing I should use boost/python/tuple.hpp or list.hpp but can't figure out the syntax. Thanks in advance.

2 2

[Thread] assertion `!pthread_mutex_lock(&m)' running threaded test
by Rush Manbert 17 Apr '09

17 Apr '09

I have this test program: ------------------------------------------- #include <iostream> #include <vector> #include <boost/thread.hpp> class TestThread { size_t m_loopCount; int m_serverPort; public: TestThread (size_t loopCount) : m_loopCount (loopCount > 0 ? loopCount : 1) , m_serverPort (9090) { return; } void operator() (void) { for (size_t loopCount = 0; loopCount < m_loopCount; ++loopCount) { // Do the same thing the socket open code does char port[6]; sprintf(port, "%d", m_serverPort); char buf0[512]; sprintf (buf0, "%s %zd", "Our loop cont is: " , loopCount); char buf1[793]; sprintf (buf1, "Now the loop count is: %zd", loopCount); // boost::this_thread::yield(); } } }; int main (int argc, char * argv[]) { unsigned int threadLoopCount = 20000; unsigned int threadCount = 2500; // Thread storage std::vector<boost::thread *> threadVec; for (size_t i = 0; i < 1; ++i) { std::cout << i << ": Spawn " << threadCount << " threads with loop count = " << threadLoopCount << std::endl; for (size_t i = 0; i < threadCount; ++i) { TestThread theThread(threadLoopCount); threadVec.push_back (new boost::thread (theThread)); } while (false) <<<-----------------------------------------This block of code disabled { threadVec.at(0)->join(); delete threadVec.at(0); threadVec.erase(threadVec.begin()); TestThread theThread(threadLoopCount); threadVec.push_back (new boost::thread (theThread)); } for (size_t i = 0; i < threadVec.size(); ++i) { threadVec.at(i)->join(); <<<<-----------------------------Error location 1 delete threadVec.at(i); <<<<-----------------------------Error location 2 } threadVec.clear(); std::cout << "Done" << std::endl; } } ------------------------------------------- I haven't edited it to remove disabled code. Note the while(false) which disables the block of code that was starting a new thread as soon as one completed. What the thread code actually does is designed to reveal a different problem. The for loop that only executes once was a failed attempt to make the desired error happen more often. If I run this program enough times in the Xcode debugger, I eventually see the error: ./boost/thread/pthread/mutex.hpp:50: failed assertion `! pthread_mutex_lock(&m)' In the latest case, this happened at the line I have labeled as "Error location 1", but I have also seen this at the line labeled as "Error location 2". I have seen other threads regarding similar errors with boost threads, but nothing says that this was a bug that has been fixed, or that there is something I should do to avoid the error. I'm also wondering if I have misunderstood something about how to use the threads code. I am running Boost 1.36.0 on OSX 10.5.6 with Xcode 3.1.2. Does this look like pilot error, or is it a bug? - Rush

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[program_options] Multitoken and positional options; assertion failure
by Gevorg Voskanyan 17 Apr '09

17 Apr '09

I was playing with program_options in svn trunk after recent fixes for multitoken options and hit an assertion failure with the attached example. The example takes two options - one multitoken and one positional, and simply outputs provided values. The two invocations below work OK: $ bin/gcc-4.2.2/debug/multitoken_positional some_file -m token1 token2 File: some_file Multitoken: token1 token2 $ bin/gcc-4.2.2/debug/multitoken_positional -m token1 token2 --file some_file File: some_file Multitoken: token1 token2 While experimenting with this one asserts: $ bin/gcc-4.2.2/debug/multitoken_positional -m token1 token2 -- some_file multitoken_positional: ../../../../../svn_boost/trunk/libs/program_options/src/cmdline.cpp:295: std::vector<boost::program_options::basic_option<char>, std::allocator<boost::program_options::basic_option<char> > > boost::program_options::detail::cmdline::run(): Assertion `opt2.original_tokens.size() == 1' failed. Aborted Should an exception be thrown instead, or this is a use-case worth to support? Thanks, Gevorg

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[boost-users][bind, lambda, ...] binding unused actual parameter
by Igor R 16 Apr '09

16 Apr '09

Hello, Is it possible somehow to make a binder that stores "unexpected" argument? Motivation: I have to create & pass a callback handler from within intusively ref-counted object (MS-ATL) to an outer asynchronous subsystem. If the object were shared-ptr enabled, I'd do this as usually: ThisObj::handler() { //... } ThisObj::doSomething() { asyncSubsystem_->doSomething(&ThisObj::handler, shared_from_this()); } However, in my case I have to do something like this: asyncSubsystem_->doSomething(&ThisObj::handler, this, mySmartPtr); // store someOtherSmartPtr in the functor, just to ensure "this" won't die before the handler is invoked Is it possible with bind, lambda or some other library? Thanks.

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[filesystem] doc bug
by Michael Fawcett 16 Apr '09

16 Apr '09

A co-worker of mine who usually programs in C# ran across this bug in the filesystem Two Minute Tutorial located here: http://www.boost.org/doc/libs/1_38_0/libs/filesystem/doc/index.htm#tutorial #include "boost/filesystem.hpp" // includes all needed Boost.Filesystem declarations #include <iostream> // for std::cout using boost::filesystem; // for ease of tutorial presentation; // a namespace alias is preferred practice in real code Should be: #include "boost/filesystem.hpp" // includes all needed Boost.Filesystem declarations #include <iostream> // for std::cout using namespace boost::filesystem; // for ease of tutorial presentation; // a namespace alias is preferred practice in real code Note the using statement. --Michael Fawcett

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Re: [Boost-users] Multiple Multitokens
by David Doria 16 Apr '09

16 Apr '09

Volodya, So was my example code way off? Ie. is the short answer that program_options can't take --list a.txt b.txt --list c.txt d.txt and give me 2 vector<string>'s, one containing a.txt b.txt and the other containing c.txt d.txt? Thanks, David

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Covariant return type, method hiding, and shared_ptr advice
by Dominique Devienne 16 Apr '09

16 Apr '09

(follow up to the "How to obtain shared_ptr<Derived> from shared_ptr<Base>?" post) class Ident { ... }; class Object { Ident* ident() { return ident_.get(); } const Ident* ident() const { return ident_.get(); } shared_ptr<Ident> ident_ptr() { return ident_; } private: shared_ptr<Ident> ident_; }; class VehicleIdent : public Ident { /* Vehicle-specific ident members */ } class Vehicle : public Object { // covariant return type VehicleIdent* ident() { return polymorphic_downcast<VehicleIdent*>(Object::ident()); } const VehicleIdent* ident() const { /* same as above */ } }; In the class hierarchy above, I return both raw and shared_ptr of an object's identity, something that opens up the possibility for bugs were the raw pointers is deleted or stuffed into another "unrelated" smart pointers. But on the other hand, when I'm dealing with a Vehicle (corrected spelling ;) instead of an Object, I'd like to get it's ident with the proper type (VehicleIdent), to access the vehicule-specific identity naturally (those methods are not shown here). So I used covariant return type, which AFAIK works only for raw pointers. If I were to remove the raw pointer accessors, I'd have to do either: class Object { shared_ptr<Ident> ident() { return ident_; } }; class Vehicle : public Object { shared_ptr<VehicleIdent> vehicule_ident() { ... } }; i.e. have a new method each time, which is less uniform, or: class Object { shared_ptr<Ident> ident() { return ident_; } }; class Vehicle : public Object { shared_ptr<VehicleIdent> ident() { ... } }; which hides the base ident() in the derive classes. What is the best alternative? Or is there a better way to deal with this? Thanks, --DD PS: is returning a const shared_ptr<T>& is better/worse than a copy?

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Re: [Boost-users] Multiple Multitokens
by David Doria 16 Apr '09

16 Apr '09

Volodya, thanks for the help thus far, I think I am close to getting it to work. According to the post you referred me to, multiple of the same parameter are not collapsed, ie --list a.txt b.txt --list c.txt d.txt Should give me access to the two separate lists. I tried declaring the parameter as usual: ("list", po::value<vector<string> >()->multitoken(), "Lists.") And then I thought it may be the .count property? cout << "There are " << vm.count("list") << " lists." << endl; But there is only 1 list. The idea was to do this: vector<vector<string> > lists; for(unsigned int list = 0; list < vm.count("list"); list++) { vector<string> l = vm["list"].as<vector<string> >(); lists.push_back(l); for(unsigned int item = 0; item < lists[list].size(); item++) cout << "List: " << list << " Item: " << item << " " << lists[list][item] << endl; } Clearly I am still missing the part about accessing the separated "list" params. Can you see the problem here? Thanks, David > > David Doria wrote: > > > I want to do something like this: > > --NumLists 2 --List0 a.txt b.txt --List1 c.txt d.txt > > > > vector<vector<string> > Lists(2); > > > > po::options_description desc("Allowed options"); > > desc.add_options() > > ("help", "produce help message") > > ("List0", po::value<vector<string> > >(&Lists[0])->multitoken(), > > "List0.") > > ("List1", po::value<vector<string> > >(&Lists[1])->multitoken(), > > "List1.") > > ; > > > > But if I wanted to handle --NumLists 10, I would have to manually add > List0, > > List1, ... List10 as parameters. That seems a bit silly, but maybe this > is a > > very odd usage? > > Well, it's somewhat odd :-) > > > Please let me know if you can think of a better way to > > handle this. > > Well, as a remark, your command line interface will make users cry: > > - Do you really want users to type uppercase letters? (Use can use > case-insensitive mode, of course, and allow any spelling, but upper > case in your example seems strange. > - Do you really want users to count lists and pass 0, 1, 2, etc explicitly? > - Why do you need explicit specification of the number of lists? > > I'd use: > > --list a.txt b.txt --list c.txt d.txt > > You might find the recent thread useful for handling such command lines: > > http://permalink.gmane.org/gmane.comp.lib.boost.user/46405 > > - Volodya > > >

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Re: [Boost-users] default argument and call trait const_reference
by Hicham Mouline 16 Apr '09

16 Apr '09

>I apologize, I didn't replace all names to make code more readable... >It was just P ... that was P's ctor... >It's Get, not GetSpot >x.template Get<P,P>( 5 ); >I've added to default argument to the out-of-class definition as well >and then it works... >does it make any sense? >H I put the code here: http://codepad.org/6tLNKGvO 1) g++3.4 complains about putting the default parameters in the declaration and the definition of GetSpot<> 2) VS2005 compiles it fine. As I said in my previous email, when the default parameter "Interp()" is not put in the definition of GetSpot<> debugging shows that "i" has not been constructed properly. When I add "Interp()" to the definition also, debugs works fine. In Release, the same behaviour is observed. Regards,

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BGL: Debug too slow
by John Krajewski 16 Apr '09

16 Apr '09

It seems my debug build is exteremely slow in the parts that call boost graph library functions. Is there a way I can force the boost lib files to compile with optimizations even though the rest of my app is in debug?? Cheers -John Krajewski

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tss.hpp:82: undefined reference to 'boost::detail::get_tss_data
by wuguangjun 16 Apr '09

16 Apr '09

Hello boosters: When I build boost_1_38, I use 'configure -prefix=/usr' command to put boost files in /usr/ directory. I compile Lintel a paser for cello99, a error occurs: the information is as follows: /usr/include/boost-1_38/boost/thread/tss.hpp:82: undefined reference to 'boost::detail::get_tss_data(void const*)' Is it a bug for boost or some other causes? Would anyone help me? 2009-04-15 wuguangjun

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[coroutine] Bus error on Mac OS X 10.5
by Nat Goodspeed 16 Apr '09

16 Apr '09

I've downloaded the not-yet-Boost coroutine library [1] from the Boost Vault [2]. On a couple of Linux platforms I was able to build and run example/banana.cpp -- though I had to patch noreturn.hpp for gcc 3.3 [3]. On an Intel "fall 2008" MacBook Pro running OS X 10.5.6, with Apple gcc 4.0.1, I had to comment out the MAP_ANONYMOUS mmap() flag [4] -- I don't think that flag is available in Darwin. (Obviously that patch should test for MAP_ANONYMOUS rather than simply suppressing it.) Having done that, the 'banana' example program built -- but I get a bus error trying to run it. I did find an exchange on the Apple mailing list [5] in which Kevin Van Vechten recommends #defining _XOPEN_SOURCE before #include <ucontext.h>: >> Why the bus error? What am I doing wrong? > This is a known issue where getcontext(3) is writing past the end of > the ucontext_t struct when _XOPEN_SOURCE is not defined > (rdar://problem/5578699 ). As a workaround, define _XOPEN_SOURCE > before including ucontext.h. Unfortunately, adding such a #define [6] does not resolve my bus error. The article [7] in which I found ref [5] proposes a classic-C program [8] to illustrate use of getcontext() and swapcontext(). On my Mac, that program produces a seg fault with or without #define _XOPEN_SOURCE. So my apologies: this may very well not be a Boost issue, or even a pre-Boost issue. I'm very excited to try the coroutine library, but crashing on Macs is a show-stopper for us. Has anyone else succeeded in running it on a Mac? [1] http://www.crystalclearsoftware.com/soc/coroutine/index.html [2] http://www.boostpro.com/vault/index.php?action=downloadfile&filename=boost-… [3] attached boost-coroutine.gcc33.patch [4] attached boost-coroutine.osx-mmap.patch [5] http://lists.apple.com/archives/darwin-dev/2008/Jan/msg00232.html [6] attached boost-coroutine.osx-context.patch [7] http://hjiang.net/archives/220 [8] attached swapcontext_test.c *** boost/coroutine/detail/noreturn.hpp~ Sun Aug 20 10:11:09 2006 --- boost/coroutine/detail/noreturn.hpp Fri Mar 27 17:00:00 2009 *************** *** 40,48 **** --- 40,54 ---- #if defined(__GNUC__) + #if __GNUC_MAJOR__ > 3 || (__GNUC_MAJOR__ == 3 && __GNUC_MINOR__ > 3) #define BOOST_COROUTINE_NORETURN(function) \ function __attribute__((__noreturn__)) \ /**/ + #else // gcc 3.3 + #define BOOST_COROUTINE_NORETURN(function) \ + function + /**/ + #endif // gcc 3.3 #elif defined (BOOST_MSVC) *** boost/coroutine/detail/posix_utility.hpp~ Sun Aug 20 13:11:09 2006 --- boost/coroutine/detail/posix_utility.hpp Fri Mar 27 18:52:17 2009 *************** *** 129,135 **** void * stack = ::mmap(NULL, size, PROT_EXEC|PROT_READ|PROT_WRITE, ! MAP_PRIVATE|MAP_ANONYMOUS, -1, 0 ); --- 129,135 ---- void * stack = ::mmap(NULL, size, PROT_EXEC|PROT_READ|PROT_WRITE, ! MAP_PRIVATE /*|MAP_ANONYMOUS*/, -1, 0 ); *** boost/coroutine/detail/context_posix.hpp~ Sun Aug 20 13:11:09 2006 --- boost/coroutine/detail/context_posix.hpp Fri Mar 27 20:57:44 2009 *************** *** 42,47 **** --- 42,56 ---- * NOTE2: makecontext and friends are declared obsolescent in SuSv3, but * it is unlikely that they will be removed any time soon. */ + // NOTE3 (per http://lists.apple.com/archives/darwin-dev/2008/Jan/msg00232.html) + // > Why the bus error? What am I doing wrong? + // This is a known issue where getcontext(3) is writing past the end of the + // ucontext_t struct when _XOPEN_SOURCE is not defined (rdar://problem/5578699 ). + // As a workaround, define _XOPEN_SOURCE before including ucontext.h. + // [While we could make that OSX-specific, it seems harmless enough?] + #ifndef _XOPEN_SOURCE + #define _XOPEN_SOURCE + #endif #include <ucontext.h> #include <boost/noncopyable.hpp> #include <boost/coroutine/exception.hpp> // From http://hjiang.net/archives/220 #include <signal.h> #include <stdio.h> // NOTE (per http://lists.apple.com/archives/darwin-dev/2008/Jan/msg00232.html) // > Why the bus error? What am I doing wrong? // This is a known issue where getcontext(3) is writing past the end of the // ucontext_t struct when _XOPEN_SOURCE is not defined (rdar://problem/5578699 ). // As a workaround, define _XOPEN_SOURCE before including ucontext.h. // [While we could make that OSX-specific, it seems harmless enough?] #ifndef _XOPEN_SOURCE //#define _XOPEN_SOURCE #endif #include <ucontext.h> // Signals which routine should run. volatile int g_turn; void routineOne(ucontext_t* self, ucontext_t* other) { int numbers[] = {1, 2, 3}; int i; for (i = 0; i < sizeof(numbers)/sizeof(int); ++i) { printf("Routine one: %d\n", numbers[i]); // Call other with current continuation if (g_turn != 1) { g_turn = 1; swapcontext(self, other); } } } void routineTwo(ucontext_t* self, ucontext_t* other) { int numbers[] = {-1, -2, -3}; int i; for (i = 0; i < sizeof(numbers)/sizeof(int); ++i) { printf("Routine two: %d\n", numbers[i]); if (g_turn != 2) { g_turn = 2; swapcontext(self, other); } } } int main() { // Continuations ucontext_t cont_one; ucontext_t cont_two; ucontext_t cont_main; // one stack for each thread char stack_one[SIGSTKSZ]; char stack_two[SIGSTKSZ]; // Initialize the coutinuations. cont_one.uc_link = &cont_main; cont_one.uc_stack.ss_sp = stack_one; cont_one.uc_stack.ss_size = sizeof(stack_one); cont_two.uc_link = &cont_main; cont_two.uc_stack.ss_sp = stack_two; cont_two.uc_stack.ss_size = sizeof(stack_two); getcontext(&cont_one); makecontext(&cont_one, (void (*)())routineOne, 2, &cont_one, &cont_two); getcontext(&cont_two); makecontext(&cont_two, (void (*)())routineTwo, 2, &cont_two, &cont_one); g_turn = 0; // Call routineOne with current continuation. Continue from here // after routineOne finishes. getcontext(&cont_main); if (g_turn == 0) { setcontext(&cont_one); } return 0; }

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Strange issue with boost::date_time
by Jared Lee Richardson 15 Apr '09

15 Apr '09

I'm having a strange issue with the boost::date_time library - My program runs fine with both release and debug compilations, but will not run in standalone / the command line. I.e., the program works when I run it through the MS visual studio debugger, whether the program is built with debugging symbols or not. It also ran correctly when run through dependency walker. It does not run when run without either of those, i.e. on a command line. Through print statements I determined that it is running through the initialization and crashes(windows brings up the crashed executable dialog, "This.exe has encountered a problem and needs to close.") The exact code it crashes on is the allocation of a class that contains time_durations: class TempClass { public: list<time_duration> TDList; time_duration SomeOtherDuration; }; and then crashes when allocating this object: TempClass* pTempClass; pTempClass = new TempClass; // <--- Crashes when run without debugger. The program crashes on the new. I tried putting a try/catch block around it for any exception to see if any were being hit and none are. I had tried to reproduce this issue in a much simpler program, but have not had any luck thus far - the test program always runs correctly. Any ideas or things to try? This is not the first instantiation of a time_duration(pushed into a vector a few lines before this), but may be the first instantiation of a std::list. The pointer listed above is actually a member of another class that is contained in a vector, if that matters(shouldn't). Any help? If not I can try again at creating a simpler program that exhibits the problem and paste it. Thanks, Jared

5 9

Windows linking problem
by John Dlugosz 15 Apr '09

15 Apr '09

I got an error cannot open file 'libboost_program_options-vc80-mt-1_38.lib' The file is called 'boost_program_options-vc80-mt-1_38.lib' without the extra prefix. According to the documentation, that's as it should be. So, why is the autolink feature not getting the name right? I'm not the first one to try this, for sure! --John TradeStation Group, Inc. is a publicly-traded holding company (NASDAQ GS: TRAD) of three operating subsidiaries, TradeStation Securities, Inc. (Member NYSE, FINRA, SIPC and NFA), TradeStation Technologies, Inc., a trading software and subscription company, and TradeStation Europe Limited, a United Kingdom, FSA-authorized introducing brokerage firm. None of these companies provides trading or investment advice, recommendations or endorsements of any kind. The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computer.

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[TortoiseSVN] Please upgrade if using TortoiseSVN 1.6.0
by Beman Dawes 15 Apr '09

15 Apr '09

There is a bug in TortoiseSVN 1.6.0 that can cause a log request to loop endlessly under certain conditions. When this happens an endless stream of requests is sent to the server. This may be why the svn.boost.org server is getting hammered, and response time is slow. It affects trac too, as it runs on the same server. The problem is fixed in release 1.6.1, so please upgrade to that release if you are currently running TortoiseSVN 1.6.0. Thanks, --Beman

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Help with custom smart pointer const correctness
by Dominique Devienne 15 Apr '09

15 Apr '09

Given the class design below, and the ObjectPtr smart pointer implementation, I can't instantiate ObjectPtr<T> with T = const Car because a const Car returns a shared_ptr<const CarIdent> from the ident() methods, not a shared_ptr<CarIdent> as currently implemented (see compile error at the end of this post. VS2005). >From my very limited meta-programming experience, I'm guessing I need to fix the current typedef shared_ptr<ident_type> ident_ptr; in ObjectPtr to somehow use MPL to "return" shared_ptr<typename T::ident_type const> given a const T, and shared_ptr<typename T::ident_type> given a T, but I don't know how to do that yet. If someone would be kind enough to point me in the right direction, I'd appreciate. Thanks, --DD #include <boost/static_assert.hpp> #include <boost/type_traits/is_base_of.hpp> #include <boost/shared_ptr.hpp> #include <boost/cast.hpp> #include <string> using namespace std; using namespace boost; class Object; class Ident { public: Object* object() const { return object_; } protected: Ident() : object_(0) {} ~Ident() {} friend class Object; void set_object(Object* e); private: Object* object_; }; typedef shared_ptr<Ident> IdentPtr; typedef shared_ptr<const Ident> ConstIdentPtr; class Object { public: ConstIdentPtr ident() const { return ident_; } const IdentPtr& ident() { return ident_; } protected: Object(shared_ptr<Ident> ident) : ident_(ident) { ident_->set_object(this); } virtual ~Object() { ident_->set_object(0); } private: shared_ptr<Ident> ident_; }; void Ident::set_object(Object* obj) { BOOST_ASSERT((!object_ && obj) || (object_ && !obj)); BOOST_ASSERT(!obj || obj->ident().get() == this); object_ = obj; } template <class T> shared_ptr<typename T::ident_type> ident_of(T* t) { BOOST_STATIC_ASSERT((is_base_of<Object, T>::value)); return static_pointer_cast<typename T::ident_type>(t->ident()); } template <class T> shared_ptr<typename T::ident_type const> ident_of(const T* t) { BOOST_STATIC_ASSERT((is_base_of<Object, T>::value)); return static_pointer_cast<typename T::ident_type const>(t->ident()); } template <class T> class ObjectPtr { public: typedef T object_type; // TODO remove constness typedef typename T::ident_type ident_type; typedef shared_ptr<ident_type> ident_ptr; // TODO: make const correct public: // this Ctor fails to compile if passing a const Car for example. // TODO: figure out (MPL? enable_if?) the correct ident_ptr type // based on the constness of T explicit ObjectPtr(T* obj) : ident_(ident_of(obj)) {} T* get() { return polymorphic_downcast<T*>(ident_->object()); } T* operator->() { get(); } T& operator*() { *get(); } ident_ptr ident() const { return ident_; } // TODO: Safe-Bool idiom // TODO: implicit conversion from ObjectPtr<T> to ObjectPtr<const T>? private: ident_ptr ident_; }; struct CarIdent : public Ident { string make, model; CarIdent(const string& make, const string& model) : make(make), model(model) {} }; class Car : public Object { public: typedef CarIdent ident_type; Car(const string& make, const string& model) : Object(shared_ptr<CarIdent>(new CarIdent(make, model))) {} }; void const_correct_smart_ptr(int /*argc*/, const char* /*argv*/[]) { ObjectPtr<Car> z(new Car("Nissan", "350Z")); ident_of(z.get())->model = "370Z"; // TODO: fix ident_of for smart pointers to avoid .get() // This fails to compile with: error C2664: // 'boost::shared_ptr<T>::shared_ptr(const boost::shared_ptr<T> &)' : // cannot convert parameter 1 from 'boost::shared_ptr<const Car::ident_type>' // to 'const boost::shared_ptr<CarIdent> &' // instantiated from explicit ObjectPtr(T* obj) : ident_(ident_of(obj)) {} ObjectPtr<const Car> zz(new Car("Ford", "Mustang")); }

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