- Boost - lists.preview.boost.org

matching algorithm
by Gunnar W. Klau 12 Oct '04

12 Oct '04

Hello, does anybody know whether there's an implementation to compute (maximum weight) matchings in general graphs? Thanks for any help, --gunnar--

2 1

Re: [boost] Re: [review] Formal review of
by brangdon＠cix.compulink.co.uk 12 Oct '04

12 Oct '04

In-Reply-To: <loom.20041011T172801-139(a)post.gmane.org> nesotto(a)cs.auc.dk (Thorsten Ottosen) wrote (abridged): > If there is no null in the tree, then why test for it? The test is to prevent moving a null dog to the tree. > I suspect having null is reasonable, but I explicitly requested to see > the code. There is no real code; the example was invented to illustrate the importance of post-conditions. Which is another way of putting what it says in the .pdf file you referenced: the Null Object pattern is not universally applicable. The point is general and not about the specific code. Are you claiming that Null Object is, in fact, applicable in every situation? If not, just imagine I picked an example where you agree its not applicable. If, on the other hand, you believe no such example is possible, then you surprise me. Regardless I don't think further discussion is appropriate here, because it is not crucial to the Smart Container proposal. As I said in my original message: ... this is no more an argument against ptr_vector<Dog> than it is against std::vector<Dog>. In saying that I was supporting your proposed library. Given that ptr_vector<T> behaves more like vector<T> than vector<T*>, the restriction on NULLs is logical and reasonable. -- Dave Harris, Nottingham, UK

1 0

[lambda] cw83-release vs. cw83-debug failures...
by Rene Rivera 12 Oct '04

12 Oct '04

I became a bit curious as to why two Lambda tests fail in the only release configuration for CW8.3, but don't fail in the debug tests. As seen in: http://www.meta-comm.com/engineering/boost-regression/developer/lambda.html And the really strange part is the lack of information from Boost.Test about it. It only outputs: Run output [2004-10-11 02:46:48 UTC]: **** no errors detected EXIT STATUS: 1 Which seems like a rather contradictory statement from the test system I don't really know what is going on here. But I've narrowed it down to some strange interaction when the "--" and "++" pre-ops are used. If I make the following changes the tests pass... Index: bind_tests_advanced.cpp =================================================================== RCS file: /cvsroot/boost/boost/libs/lambda/test/bind_tests_advanced.cpp,v retrieving revision 1.8 diff -u -r1.8 bind_tests_advanced.cpp --- bind_tests_advanced.cpp 27 Jul 2004 03:43:33 -0000 1.8 +++ bind_tests_advanced.cpp 12 Oct 2004 03:02:38 -0000 @@ -110,7 +110,7 @@ int i = 1; BOOST_TEST(unlambda(_1 + _2)(i, i) == 2); - BOOST_TEST(unlambda(++var(i))() == 2); + { bool t = unlambda(++var(i))() == 2; BOOST_TEST(t); } BOOST_TEST(call_with_100(_1 + 1) == 101); Index: operator_tests_simple.cpp =================================================================== RCS file: /cvsroot/boost/boost/libs/lambda/test/operator_tests_simple.cpp,v retrieving revision 1.8 diff -u -r1.8 operator_tests_simple.cpp --- operator_tests_simple.cpp 27 Jul 2004 03:43:33 -0000 1.8 +++ operator_tests_simple.cpp 12 Oct 2004 03:02:38 -0000 @@ -175,11 +175,11 @@ BOOST_TEST(i == -1); i = 0; - BOOST_TEST((++_1)(i) == 1); + { bool t = (++_1)(i) == 1; BOOST_TEST(t); } BOOST_TEST(i == 1); i = 0; - BOOST_TEST((--_1)(i) == -1); + { bool t = (--_1)(i) == -1; BOOST_TEST(t); } BOOST_TEST(i == -1); i = 0; =================================================================== Any ideas, clues, etc. ?? -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com - 102708583/icq

1 0

[ANN] Boost testing mailing list
by Misha Bergal 12 Oct '04

12 Oct '04

The boost-testing mailing list is now operational: The setup, procedures and tools necessary for running Boost regression tests are discussed on this list. The list main participants are regression runners - people who run Boost tests on a variety of compilers and platforms, and the maintainers of tools for collecting and processing test results. Important: questions relevant to a wider audience, including questions about Boost.Test framework or test results for a particular library, should be posted to main development list. You can subscribe to the list at http://lists.boost.org/mailman/listinfo.cgi/boost-testing. -- Misha Bergal MetaCommunications Engineering

3 4

filesystem::is_directory return true when exception is disabled and this directory does't exist
by Liao Weijie 12 Oct '04

12 Oct '04

// the snip of code in filesystem::is_directory begin--- DWORD attributes = ::GetFileAttributesA( ph.native_directory_string().c_str() ); if ( attributes == 0xFFFFFFFF ) boost::throw_exception( filesystem_error( "boost::filesystem::is_directory", ph, fs::detail::system_error_code() ) ); return (attributes & FILE_ATTRIBUTE_DIRECTORY) != 0; //-------------------------------------------------------end-- When GetFileAttributesA failed but the exception is disabled, the (attributes & FILE_ATTRIBUTE_DIRECTORY) will always be true. Is it a bug?

4 4

Suggestion for multi_array query information
by Anders Edin 11 Oct '04

11 Oct '04

Hello, I have a short suggestion about the interface for multi_array. It is possible to query a multi_array<T,N> for information about the storage: // queries ... const size_type* shape() const; const index* strides() const; const index* index_bases() const; ... It appears multi_array uses a boost::array internally to store this information, and uses the data() method to return a pointer in the above methods. Wouldn't it be better to return a reference to the array directly: // queries ... const array<size_type, N>& shape() const; const array<index, N>& strides() const; const array<index, N>& index_bases() const; ... With this interface the information about the number of elements of shapes and strides is not lost during the query. -- Anders Edin, Sidec Technologies AB Fogdevreten 2A, 171 77 Stockholm, Sweden Phone: +46850884525, Fax: +46850884522

2 1

Boost.String Algorithms patch
by Daniel Schlyder 11 Oct '04

11 Oct '04

The attached patch fixes invalid #include in boost/algorithm/string_regex.hpp and unused parameter warnings in boost/algorithm/string/formatter.hpp boost/algorithm/string/detail/find_format.hpp -- Daniel Schlyder http://bitblaze.com/

2 1

MPL - mpl::sequence to std::sequence
by Jaap Suter 11 Oct '04

11 Oct '04

Hi, what is the easiest way to convert an mpl::sequence to an std::sequence? I'm using such conversions a lot when unit-testing meta-code. I just wrote two versions of algorithms, a compile-time and the runtime one, and then compare their outputs. I recall hearing something about mpl::for_each having defined an operator () for runtime purposes, but the details don't seem to be documented anywhere. I came up with the attached code, of which the "to_compile_time" might actually be of general interest. It's a function that converts a runtime integer to a compile time integer. Code-generation-wise it's a horror and it could be more generic, but it gets the job done for me. I'd like to hear if there are more elegant solutions for this though, as it seems like too much code. Thanks, Jaap Suter

5 11

Preprocessor headers docs
by Aleksey Gurtovoy 11 Oct '04

11 Oct '04

Paul, Are these (from http://tinyurl.com/4hp7d) automatically generated: libs/preprocessor/doc/headers/arithmetic.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/add.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/dec.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/div.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/inc.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/mod.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/mul.hpp.html: filename contains more than one dot character ('.') libs/preprocessor/doc/headers/arithmetic/sub.hpp.html: filename contains more than one dot character ('.') ... ? If so, can we adopt a convention that doesn't involve multiple dots [1] and re-generate them? [1] E.g. "libs/preprocessor/doc/headers/arithmetic/add_hpp.html", or even, since these are in their own subdirectory anyway ("headers"), plain "libs/preprocessor/doc/headers/arithmetic/add.html". -- Aleksey Gurtovoy MetaCommunications Engineering

1 1

uBLAS results for vc7.1 too good to be true?
by Bronek Kozicki 11 Oct '04

11 Oct '04

http://www.meta-comm.com/engineering/boost-regression/developer/numeric-ubl… (http://tinyurl.com/3vmlv ) Almost all results for vc7.1 are marked "unexpected success". I think this compiler is around for enough long time to mark these results as "just expected" success? B.

3 2