- Boost - lists.boost.org

[algorithm] Knuth-Morris-Pratt Search docs overly terse
by Jeff Flinn 07 Nov '12

07 Nov '12

I'm not sure if this is intentional but: http://www.boost.org/doc/libs/1_52_0/libs/algorithm/doc/html/the_boost_algo… contains only: Overview The header file 'knuth_morris_pratt.hpp' contains an an implementation of the Knuth-Morris-Pratt algorithm for searching sequences of values. I've created Ticket #7656. Jeff

1 0

[functional] Interested in can_be_called<F, Sig> metafunction?
by TONGARI 07 Nov '12

07 Nov '12

Hi there, I've used this metafunction for some time, and it just fitted my need. Recently, I make up my mind to complete it, willing to put it in public. Synopsis -------------- can_be_called<F, Sig> F Any callable type to test, even member-function ptr. Sig The desired calling signature, function-type only. Example ------------- struct X; struct F { void operator()(); }; can_be_called<void(int), void(char)>::type // mpl::true_ can_be_called<int(), void()>::type // mpl::true_, return val can always be discarded can_be_called<int(), int&()>::type // mpl::false_, cannot return as reference can_be_called<void(int&), void(int)>::type // mpl::false_, cannot accept rvalue can_be_called<void(), void(*)()>::type // compile error, "void(*)()" not a function-type can_be_called<F, void()>::type // mpl::true_ can_be_called<F const, void()>::type // mpl::false_, F::operator() is non-const can_be_called<void(X::*)(), void()>::type // mpl::true_, only the signature part is concerned can_be_called<void(X::*)(), void(X*)>::type // mpl::false_, implicit 'this' arg not accounted Repository ---------------- https://github.com/jamboree/boost.functional test files provided, compile well on g++ 4.7.1 & clang 3.2 No docs are written (yet), if you're interested, please let me know and I'll prepare for review or something... Comments are welcome :)

6 19

[1.52] PDF Documentation build available
by John Maddock 07 Nov '12

07 Nov '12

The PDF build of Boost docs is now available for 1.52 from: https://sourceforge.net/projects/boost/files/boost-docs/1.52.0/ John.

1 0

[qvm] scalar_cast
by Nikolay Mladenov 07 Nov '12

07 Nov '12

Hi Emil, I am trying qvm in a small project that uses complex numbers and have expressions of the kind : cv3 = c1*rv3_1 + c2*rv3_2 (the v3's are vectors, the c's are complex and the r's are real). I wrote it as : cv3 = scalar_cast<complex>(rv3_1)*c1 + scalar_cast<complex>(rv3_2)*c2; but this seems to invoke 6 complex constructors (unnecessarily) I have not tested to see if the constructors will be optimized away, but it seems to me that if : v_traits<vector_scalar_cast_>::scalar_type == complex , bit v_traits<vector_scalar_cast_>::r/ir return real the expression will compile and no complex constructors will be invoked. It seems to me that there is a need for another kind of scalar_cast that just adapts the v_traits<>:scalar_type but leaves the r() and ir() unchanged Another question I have is if there is a reason why vector*scalar works but scalar*vector does not? Thanks in advance, Nikolay PS I can send patches if you'd like.

2 3

[release][1.52.0] Release Notes
by Daniel James 06 Nov '12

06 Nov '12

Hello everyone, We're coming up to the beta release, so it's time to put together the release notes (although please don't feel you need to wait for me to start). As always you can send them to me, or if you want update them yourself in subversion. The files are at: https://svn.boost.org/svn/boost/website/public_html/live/feed/history/ The actual site won't get updated until I run the update script. You can see the release notes so far at: http://www.boost.org/users/history/version_1_52_0.html As usual, they're not finished yet, and some of the links might not work as the 1.52 documentation won't be uploaded until after the beta is released. thanks, Daniel

9 22

[clang] Windows toolset support?
by Beman Dawes 06 Nov '12

06 Nov '12

Cygwin has been shipping clang for six months or so. Has anyone gotten the cygwin/clang distribution (or any other clang distribution) to build boost? What toolset did you use? What does your user-config.jam file look like? Do you run bjam/b2 from the Windows command line or the bash command line? Thanks, --Beman

7 16

make_shared_array
by Peter Dimov 06 Nov '12

06 Nov '12

Hello, Glen Fernandes has kindly contributed an implementation of make_shared_array and allocate_shared_array. These are like make_shared and allocate_shared, except that they take a size_t argument N and allocate an array of N elements. Glen has made the functions return a shared_ptr, mostly because they are non-intrusive and it's not possible to return a shared_array without changes to shared_ptr and shared_array. But we can make such changes when we put the functions in Boost. So the question is, should we? It makes almost no sense to have a function called make_shared_array that does not, in fact, make a shared_array. On the other hand, Glen posits that some people may prefer to use shared_ptr instead of shared_array in their code for various reasons, one of which is that shared_array's default constructor can throw. Opinions?

9 40

hierarchy_tree container
by Morgan Freeberg 06 Nov '12

06 Nov '12

Ready to assess the level of interest and look into the possibility of a preliminary submission on my container library. I needed something to organize objects of type T, into a simple tree with parent-child relationships, which could then be filtered and listed. Also needed the container to maintain a "current add" position if you will, much like an output file stream, so I could feed tree structure data into it, for example as when reading from XML. I have the logic for this nicely separated into a header that seems to meet all the Boost coding guidelines, although I know a peer review process would likely yield helpful improvements that aren't immediately obvious to me. The doc file I prepared goes into much greater detail how this all works...would there be interest in looking into such a thing?

2 1

[type_traits] possible regression on is_function trait
by Vicente J. Botet Escriba 06 Nov '12

06 Nov '12

Hi, I don't know if this is a regression on Boost.TypeTraits or if I'm using incorrectly the is_function trait. John, could you confirm there is a bug in is_function? Best, Vicente Test output: Sandia-darwin-4.4 - thread - async__async_p / darwin-4.4 Rev 81191 / Mon, 5 Nov 2012 06:30:00 +0000 *Report Time: *Mon, 5 Nov 2012 14:19:58 +0000 Compile [2012-11-05 07:50:44 UTC]: fail "/opt/local/bin/g++-mp-4.4" -ftemplate-depth-128 -O0 -fno-inline -Wall -pedantic -g -dynamic -gdwarf-2 -fexceptions -fPIC -Wextra -Wno-long-long -fpermissive -pedantic -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -DBOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED -DBOOST_THREAD_USE_DLL=1 -I".." -c -o "/Volumes/scratch/kbelco/boost/results/boost/bin.v2/libs/thread/test/async__async_p.test/darwin-4.4/debug/threading-multi/sync/futures/async/async_pass.o" "../libs/thread/test/sync/futures/async/async_pass.cpp" In file included from ../boost/type_traits/is_convertible.hpp:28, from ../boost/thread/detail/move.hpp:13, from ../boost/thread/future.hpp:20, from ../libs/thread/test/sync/futures/async/async_pass.cpp:28: ../boost/type_traits/is_function.hpp: In instantiation of 'boost::detail::is_function_chooser<false>::result_<boost::rv<boost::rv<boost::packaged_task<int()> > >&>': ../boost/type_traits/is_function.hpp:60: instantiated from 'boost::detail::is_function_impl<boost::rv<boost::rv<boost::packaged_task<int()> > >&>' ../boost/type_traits/is_function.hpp:102: instantiated from 'boost::is_function<boost::rv<boost::rv<boost::packaged_task<int()> > >&>' ../boost/type_traits/is_convertible.hpp:354: instantiated from 'const bool boost::detail::is_convertible_impl<boost::rv<boost::packaged_task<int()> >&, boost::rv<boost::rv<boost::packaged_task<int()> > >&>::value' ../boost/type_traits/is_convertible.hpp:480: instantiated from 'boost::is_convertible<boost::rv<boost::packaged_task<int()> >&, boost::rv<boost::rv<boost::packaged_task<int()> > >&>' ../boost/thread/future.hpp:2717: instantiated from 'boost::future<T> boost::async(boost::launch, R (*)()) [with R = int]' ../libs/thread/test/sync/futures/async/async_pass.cpp:117: instantiated from here ../boost/type_traits/is_function.hpp:52: error: forming pointer to reference type 'boost::rv<boost::rv<boost::packaged_task<int()> > >&'

3 5

[test] BOOST_TEST - universal testing tool
by Gennadiy Rozental 06 Nov '12

06 Nov '12

Hi, Based on a discussion on mini-review thread I make some changes to the universal testing tool interface and now it look as follows (similar interfaces on WARN and REQUIRE levels): BOOST_CHECK_ASSERTION(A) - new expression template based testing tool BOOST_TEST(A,M) := BOOST_CHECK_ASSERTION(A) if M is not supplied or BOOST_CHECK_MESSAGE(A,M) if M is supplied. BOOST_TEST (and it's siblings BOOST_TEST_WARN and BOOST_TEST_REQUIRE) is intended to become a primary (only?) testing tools from now on. It replaces and deprecates right away following tools: BOOST_CHECK BOOST_CHECK_MESSAGE BOOST_CHECK_EQUAL, BOOST_CHECK_NE, BOOST_CHECK_LT, BOOST_CHECK_LE, BOOST_CHECK_GT, BOOST_CHECK_GE There are still some tools which are not directly replaceable. I have some ideas how we can get there, but your input is appreciated: 1. BOOST_CHECK_THROW, BOOST_CHECK_EXCEPTION, BOOST_CHECK_NO_THROW We can probably leave these as is. Alternatively we'll need to postpone expression evaluation with separate BOOST_TEST_DELAYED tool. We also need to introduce special tags unit_test::throws, unit_test::no_throw: BOOST_TEST_DELAYED(foo(), unit_test::throws<my_exception>() ); BOOST_TEST_DELAYED(foo(), unit_test::throws<my_exception>(predicate) ); BOOST_TEST_DELAYED(foo(), unit_test::throws( my_exception(...) ) ); BOOST_TEST_DELAYED(foo(), unit_test::no_throw() ); Later form will match to exact exception value. We might be able to fit into BOOST_TEST interface, but that would require somehow we need to recognize executable entity as special case: BOOST_TEST( foo, unit_test::throws<my_exception>() ); Not quite sure if this is possible. 2. BOOST_CHECK_CLOSE, BOOST_CHECK_CLOSE_FRACTION, BOOST_CHECK_SMALL We can deal with these by introducing couple special tags: BOOST_TEST(a == 1.5, unit_test::tolerance(1e-6) ); BOOST_TEST(a == 0.003, unit_test::percent_tolerance(1e-6) ); BOOST_TEST(a, unit_test::small(1e-3) ); On a plus side we'll be able to use these in new previously unavailable way: BOOST_TEST(a > 1.1, unit_test::tolerance(1e-6) ); This would test that value of a either > 1.1 or within a fraction tolerance of it. 3. BOOST_CHECK_PREDICATE Similar to (1) we need to delay predicate execution. Might be easier to leave it be. 4. BOOST_CHECK_EQUAL_COLLECTIONS I think using overloading of equality comparisons we should be able to support this directly: BOOST_TEST( expr == std::vector<int>{1,2,3,4}); 5. BOOST_CHECK_BITWISE_EQUAL We can introduce yet another tag to deal with this: BOOST_TEST(a == 0xA1FB, unit_test::bitwise ); As usual any comments are welcome. Gennadiy

7 16