May 2016 - Boost-users - lists.preview.boost.org

[interprocess] Determine size of managed_shared_memory
by Kai Benndorf 12 Oct '19

12 Oct '19

Hi all, I want to create a managed_shared_memory in exactly the size I needed. Therefore I do something like this: size = sizeof( common_managed_shared_memory ); size += sizeof( MyClassInSharedMem ); managed_shared_memory segment(create_only, "name", size ); MyClassInSharedMem allocates itself some memory by segment->allocate(). I added this also to the size, but get a boost::interprocess::bad_alloc exception on allocating this additional memory. Are there some magic bytes I forgot to add? Many thanks in advance Kai

3 2

Weird compilation error when using boost::geometry
by 邓尧 16 Nov '17

16 Nov '17

Hi, I have implemented my own "point" as specified by the point concept http://www.boost.org/doc/libs/1_59_0/libs/geometry/doc/html/geometry/refere… When I use it along with boost::geometry::model::polygon/multi_polygon, GCC refuses to compile, tested on GCC 4.9/5.2. What's even more weird is that CLANG 3.6 would happy accept my code. BTW, the Point implementation is part of a large project, it difficult to replace it with boost::geometry::model::point. Here is my code: Point.hpp > #ifndef RAPTOR_POINT_HPP_INCLUDED_ > > #define RAPTOR_POINT_HPP_INCLUDED_ > > >> #include <boost/mpl/int.hpp> > > #include <boost/geometry/core/access.hpp> > > #include <boost/geometry/core/cs.hpp> > > #include <boost/geometry/core/coordinate_type.hpp> > > #include <boost/geometry/core/coordinate_system.hpp> > > #include <boost/geometry/core/coordinate_dimension.hpp> > > #include <boost/geometry/geometries/polygon.hpp> > > #include <boost/geometry/multi/geometries/multi_polygon.hpp> > > >> namespace raptor { > > >> template<typename T, int tDimension = 2> > > class Point { > > public: > > Point() = default; > > >> Point(T a, T b) { > > data[0] = a; > > data[1] = b; > > } > > >> Point(T a, T b, T c) { > > data[0] = a; > > data[1] = b; > > data[2] = c; > > } > > >> T& operator [] (long index) { > > return data[index]; > > } > > >> const T& operator [] (long index) const { > > return data[index]; > > } > > >> private: > > T data[tDimension]; > > }; > > >> using CubicPoint = Point<long, 3>; > > using PlanarPoint = Point<long>; > > using SphericalPoint = Point<double>; > > >> template<typename T> > > using Polygon = boost::geometry::model::polygon<T>; > > >> template<typename T> > > using PolySet = boost::geometry::model::multi_polygon<Polygon<T>>; > > >> } // namespace raptor > > >> namespace boost { namespace geometry { namespace traits { > > >> template<typename Type, std::size_t tDimension> > > struct tag<::raptor::Point<Type, tDimension>> { > > typedef point_tag type; > > }; > > >> template<typename Type, std::size_t tDimension> > > struct coordinate_type<::raptor::Point<Type, tDimension>> { > > typedef Type type; > > }; > > >> template<typename Type, std::size_t tDimension> > > struct coordinate_system<::raptor::Point<Type, tDimension>> { > > typedef boost::geometry::cs::cartesian type; > > }; > > >> template<typename Type, std::size_t tDimension> > > struct dimension<::raptor::Point<Type, tDimension>> > > : public boost::mpl::int_<tDimension> { > > // EMPTY > > }; > > >> template<typename Type, std::size_t tDimension, std::size_t tIndex> > > struct access<::raptor::Point<Type, tDimension>, tIndex> { > > static Type get(const ::raptor::Point<Type, tDimension>& p) { > > return p[tIndex]; > > } > > >> static void set(::raptor::Point<Type, tDimension>& p, > > const Type& value) { > > p[tIndex] = value; > > } > > }; > > >> }}} // namespace boost::geometry::traits > > >> #endif // RAPTOR_POINT_HPP_INCLUDED_ > > A real simple main.cpp: > #include "Point.hpp" > > >> int main() { > > raptor::Polygon<raptor::SphericalPoint> pl; > > raptor::PolySet<raptor::SphericalPoint> set; > > return sizeof(pl) + sizeof(set); > > } > > > GCC compilation error: g++ main.cpp -std=c++14 > In file included from /usr/include/boost/geometry/core/access.hpp:20:0, from Point.hpp:5, from main.cpp:1: /usr/include/boost/geometry/core/point_type.hpp: In instantiation of > 'struct boost::geometry::traits::point_type<raptor::Point<double> >': /usr/include/boost/geometry/core/point_type.hpp:66:17: required from > 'struct boost::geometry::core_dispatch::point_type<void, > raptor::Point<double> >' /usr/include/boost/geometry/core/coordinate_type.hpp:58:62: required from > 'struct boost::geometry::core_dispatch::coordinate_type<void, > raptor::Point<double> >' /usr/include/boost/geometry/core/coordinate_type.hpp:92:25: required from > 'struct boost::geometry::coordinate_type<raptor::Point<double> >' /usr/include/boost/geometry/geometries/concepts/point_concept.hpp:90:54: > required from 'class boost::geometry::concept::Point<raptor::Point<double> > >' /usr/include/boost/concept/detail/has_constraints.hpp:32:62: required by > substitution of 'template<class Model> boost::concepts::detail::yes > boost::concepts::detail::has_constraints_(Model*, > boost::concepts::detail::wrap_constraints<Model, (& Model:: constraints)>*) > [with Model = boost::geometry::concept::Point<raptor::Point<double> >]' /usr/include/boost/concept/detail/has_constraints.hpp:42:5: required from > 'const bool > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >::value' /usr/include/boost/concept/detail/has_constraints.hpp:45:31: required > from 'struct > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >' /usr/include/boost/mpl/if.hpp:67:11: required from 'struct > boost::mpl::if_<boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >, > boost::concepts::constraint<boost::geometry::concept::Point<raptor::Point<double> > > >, boost::concepts::requirement<boost::concepts::failed************ > boost::geometry::concept::Point<raptor::Point<double> >::************> >' /usr/include/boost/concept/detail/general.hpp:50:8: required from 'struct > boost::concepts::requirement_<void > (*)(boost::geometry::concept::Point<raptor::Point<double> >)>' /usr/include/boost/geometry/geometries/ring.hpp:60:5: required from > 'class boost::geometry::model::polygon<raptor::Point<double>, true, true, > std::vector, std::vector, std::allocator, std::allocator>' main.cpp:4:42: required from here /usr/include/boost/geometry/core/point_type.hpp:45:5: error: no matching > function for call to 'assertion_failed(mpl_::failed************ > (boost::geometry::traits::point_type<raptor::Point<double> > >::NOT_IMPLEMENTED_FOR_THIS_POINT_TYPE::************)(mpl_::assert_::types<raptor::Point<double>, > mpl_::na, mpl_::na, mpl_::na>))' BOOST_MPL_ASSERT_MSG ^ /usr/include/boost/mpl/assert.hpp:82:5: note: candidate: template<bool C> > int mpl_::assertion_failed(typename mpl_::assert<C>::type) int assertion_failed( typename assert<C>::type ); ^ /usr/include/boost/mpl/assert.hpp:82:5: note: template argument > deduction/substitution failed: /usr/include/boost/geometry/core/point_type.hpp:45:5: note: cannot > convert > 'boost::geometry::traits::point_type<Geometry>::NOT_IMPLEMENTED_FOR_THIS_POINT_TYPE48::assert_arg<raptor::Point<double> > >()' (type 'mpl_::failed************ > (boost::geometry::traits::point_type<raptor::Point<double> > >::NOT_IMPLEMENTED_FOR_THIS_POINT_TYPE::************)(mpl_::assert_::types<raptor::Point<double>, > mpl_::na, mpl_::na, mpl_::na>)') to type 'mpl_::assert<false>::type {aka > mpl_::assert<false>}' BOOST_MPL_ASSERT_MSG ^ In file included from > /usr/include/boost/geometry/core/coordinate_type.hpp:21:0, from /usr/include/boost/geometry/core/access.hpp:24, from Point.hpp:5, from main.cpp:1: /usr/include/boost/geometry/core/point_type.hpp: In instantiation of > 'struct boost::geometry::core_dispatch::point_type<void, > raptor::Point<double> >': /usr/include/boost/geometry/core/coordinate_type.hpp:58:62: required from > 'struct boost::geometry::core_dispatch::coordinate_type<void, > raptor::Point<double> >' /usr/include/boost/geometry/core/coordinate_type.hpp:92:25: required from > 'struct boost::geometry::coordinate_type<raptor::Point<double> >' /usr/include/boost/geometry/geometries/concepts/point_concept.hpp:90:54: > required from 'class boost::geometry::concept::Point<raptor::Point<double> > >' /usr/include/boost/concept/detail/has_constraints.hpp:32:62: required by > substitution of 'template<class Model> boost::concepts::detail::yes > boost::concepts::detail::has_constraints_(Model*, > boost::concepts::detail::wrap_constraints<Model, (& Model:: constraints)>*) > [with Model = boost::geometry::concept::Point<raptor::Point<double> >]' /usr/include/boost/concept/detail/has_constraints.hpp:42:5: required from > 'const bool > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >::value' /usr/include/boost/concept/detail/has_constraints.hpp:45:31: required > from 'struct > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >' /usr/include/boost/mpl/if.hpp:67:11: required from 'struct > boost::mpl::if_<boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >, > boost::concepts::constraint<boost::geometry::concept::Point<raptor::Point<double> > > >, boost::concepts::requirement<boost::concepts::failed************ > boost::geometry::concept::Point<raptor::Point<double> >::************> >' /usr/include/boost/concept/detail/general.hpp:50:8: required from 'struct > boost::concepts::requirement_<void > (*)(boost::geometry::concept::Point<raptor::Point<double> >)>' /usr/include/boost/geometry/geometries/ring.hpp:60:5: required from > 'class boost::geometry::model::polygon<raptor::Point<double>, true, true, > std::vector, std::vector, std::allocator, std::allocator>' main.cpp:4:42: required from here /usr/include/boost/geometry/core/point_type.hpp:66:17: error: no type named > 'type' in 'struct boost::geometry::traits::point_type<raptor::Point<double> > >' >::type type; ^ In file included from > /usr/include/boost/geometry/geometries/polygon.hpp:26:0, from Point.hpp:10, from main.cpp:1: /usr/include/boost/geometry/geometries/concepts/point_concept.hpp: In > instantiation of 'class > boost::geometry::concept::Point<raptor::Point<double> >': /usr/include/boost/concept/detail/has_constraints.hpp:32:62: required by > substitution of 'template<class Model> boost::concepts::detail::yes > boost::concepts::detail::has_constraints_(Model*, > boost::concepts::detail::wrap_constraints<Model, (& Model:: constraints)>*) > [with Model = boost::geometry::concept::Point<raptor::Point<double> >]' /usr/include/boost/concept/detail/has_constraints.hpp:42:5: required from > 'const bool > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >::value' /usr/include/boost/concept/detail/has_constraints.hpp:45:31: required > from 'struct > boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >' /usr/include/boost/mpl/if.hpp:67:11: required from 'struct > boost::mpl::if_<boost::concepts::not_satisfied<boost::geometry::concept::Point<raptor::Point<double> > > >, > boost::concepts::constraint<boost::geometry::concept::Point<raptor::Point<double> > > >, boost::concepts::requirement<boost::concepts::failed************ > boost::geometry::concept::Point<raptor::Point<double> >::************> >' /usr/include/boost/concept/detail/general.hpp:50:8: required from 'struct > boost::concepts::requirement_<void > (*)(boost::geometry::concept::Point<raptor::Point<double> >)>' /usr/include/boost/geometry/geometries/ring.hpp:60:5: required from > 'class boost::geometry::model::polygon<raptor::Point<double>, true, true, > std::vector, std::vector, std::allocator, std::allocator>' main.cpp:4:42: required from here /usr/include/boost/geometry/geometries/concepts/point_concept.hpp:93:10: > error: 'value' is not a member of > 'boost::geometry::dimension<raptor::Point<double> >' enum { ccount = dimension<Geometry>::value }; ^ Where is the problem ? or it's a GCC bug ? Thanks

3 4

[Range, Phoenix] What am I missing...
by Robert Jones 25 Apr '17

25 Apr '17

Hi Folks Can anyone explain the output of this program... #include <iostream> #include <boost/range/algorithm/copy.hpp> #include <boost/range/counting_range.hpp> #include <boost/range/adaptor/reversed.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/phoenix/core/argument.hpp> int f( int i ) { return i * 2; } int main( ) { using boost::adaptors::reversed; using boost::adaptors::transformed; using boost::counting_range; using boost::copy; using boost::phoenix::arg_names::_1; copy( counting_range( 1, 5 ) | reversed | transformed( f ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; copy( counting_range( 1, 5 ) | reversed | transformed( bind( f, _1 ) ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; } Which is... 8 6 4 2 1768406272 1768406272 1768406272 1768406272 I'm using Gcc 4.6.2 & Boost 1.53 Thx All.

3 4

[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example. typename sc = boost::statechart; class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; }; class MyStateMachine; class StSource; class StTarget; class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } }; class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; }; Thanks, Christophe

5 6

Boost fusion problem
by Jess Morecroft 05 Jun '16

05 Jun '16

Hi guys, We're trying out the latest version of Boost (1.61, migrating from 1.55) and have some code calling the fusion library that now doesn't compile and it's not obvious (to me at least) why. I've created a simple program (below) to demonstrate the issue. As per the compile/run section below, this compiles and runs with Boost 1.55, not with 1.61. If anyone has any idea or pointers to what is wrong here I'd really appreciate it. Sorry if this isn't the right forum for this kind of issue too - if so please let me know how best to seek help on this. Regards Jess ******************** main.cpp #include <boost/fusion/algorithm/iteration/for_each.hpp> #include <boost/fusion/view/zip_view.hpp> #include <boost/fusion/tuple.hpp> #include <iostream> #include <string> struct Helper { template<typename Arg> void operator()(const Arg& arg) const { std::cout << boost::fusion::get<0>(arg) << std::endl; std::cout << boost::fusion::get<1>(arg) << std::endl; } }; int main() { const int myint(123); const double mydub(456.0); const std::string mystr("blah"); const bool mybool(false); typedef boost::fusion::tuple<const int&, const double&> Tuple1; typedef boost::fusion::tuple<const std::string&, const bool&> Tuple2; typedef boost::fusion::tuple<const Tuple1&, const Tuple2&> Tuple3; Helper helper; boost::fusion::for_each( boost::fusion::zip_view<Tuple3>( Tuple3(Tuple1(myint, mydub), Tuple2(mystr, mybool))), helper); return 0; } ******************** compile/run tests jess@flathead:~$ g++ --version g++ (Ubuntu 5.3.1-14ubuntu2) 5.3.1 20160413 Copyright (C) 2015 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. (boost 1.55) jess@flathead:~$ g++ -std=c++14 main.cpp jess@flathead:~$ ./a.out 123 blah 456 0 (boost 1.61) jess@flathead:~$ g++ -std=c++14 main.cpp In file included from /usr/local/include/boost/fusion/container/vector/vector10.hpp:25:0, from /usr/local/include/boost/fusion/view/transform_view/transform_view.hpp:22, from /usr/local/include/boost/fusion/algorithm/transformation/transform.hpp:11, from /usr/local/include/boost/fusion/view/zip_view/detail/begin_impl.hpp:14, from /usr/local/include/boost/fusion/view/zip_view/zip_view.hpp:16, from /usr/local/include/boost/fusion/view/zip_view.hpp:12, from main.cpp:2: /usr/local/include/boost/fusion/container/vector/vector.hpp: In instantiation of ‘constexpr boost::fusion::vector_detail::vector_data<std::integer_sequence<long unsigned int, _Idx ...>, T ...>::vector_data(boost::fusion::vector_detail::each_elem, U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; long unsigned int ...I = {0ul, 1ul}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’: /usr/local/include/boost/fusion/container/vector/vector.hpp:305:97: required from ‘boost::fusion::vector<T>::vector(U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’ /usr/local/include/boost/fusion/view/zip_view/zip_view.hpp:128:30: required from ‘constexpr boost::fusion::zip_view<Sequences>::zip_view(const Sequences&) [with Sequences = boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>]’ main.cpp:32:64: required from here /usr/local/include/boost/fusion/container/vector/vector.hpp:230:52: error: mismatched argument pack lengths while expanding ‘boost::fusion::vector_detail::store<I, T>’ : store<I, T>(std::forward<U>(var))... ^ /usr/local/include/boost/fusion/container/vector/vector.hpp: In instantiation of ‘constexpr boost::fusion::vector_detail::store<<anonymous>, T>::store() [with long unsigned int <anonymous> = 0ul; T = const boost::fusion::tuple<const int&, const double&>&]’: /usr/local/include/boost/fusion/container/vector/vector.hpp:230:52: required from ‘constexpr boost::fusion::vector_detail::vector_data<std::integer_sequence<long unsigned int, _Idx ...>, T ...>::vector_data(boost::fusion::vector_detail::each_elem, U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; long unsigned int ...I = {0ul, 1ul}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’ /usr/local/include/boost/fusion/container/vector/vector.hpp:305:97: required from ‘boost::fusion::vector<T>::vector(U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’ /usr/local/include/boost/fusion/view/zip_view/zip_view.hpp:128:30: required from ‘constexpr boost::fusion::zip_view<Sequences>::zip_view(const Sequences&) [with Sequences = boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>]’ main.cpp:32:64: required from here /usr/local/include/boost/fusion/container/vector/vector.hpp:137:24: error: value-initialization of reference type ‘const boost::fusion::tuple<const int&, const double&>&’ : elem() // value-initialized explicitly ^ /usr/local/include/boost/fusion/container/vector/vector.hpp: In instantiation of ‘constexpr boost::fusion::vector_detail::store<<anonymous>, T>::store() [with long unsigned int <anonymous> = 1ul; T = const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&]’: /usr/local/include/boost/fusion/container/vector/vector.hpp:230:52: required from ‘constexpr boost::fusion::vector_detail::vector_data<std::integer_sequence<long unsigned int, _Idx ...>, T ...>::vector_data(boost::fusion::vector_detail::each_elem, U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; long unsigned int ...I = {0ul, 1ul}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’ /usr/local/include/boost/fusion/container/vector/vector.hpp:305:97: required from ‘boost::fusion::vector<T>::vector(U&& ...) [with U = {const boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>&}; T = {const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&}]’ /usr/local/include/boost/fusion/view/zip_view/zip_view.hpp:128:30: required from ‘constexpr boost::fusion::zip_view<Sequences>::zip_view(const Sequences&) [with Sequences = boost::fusion::tuple<const boost::fusion::tuple<const int&, const double&>&, const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&>]’ main.cpp:32:64: required from here /usr/local/include/boost/fusion/container/vector/vector.hpp:137:24: error: value-initialization of reference type ‘const boost::fusion::tuple<const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&, const bool&>&’

2 3

installing on a local 2 core system
by Salvador Aguiñaga 30 May '16

30 May '16

> Installing on small system I want to use for temporary development, I get the following error. > > >parallel-bgl-0.7.0/boost/property_map/property_map.hpp:16:37: fatal error: boost/pending/cstddef.hpp: No such file or directory > compilation terminated > > I've configured the system: > >"sudo apt-get install build-essential" > > And successfully installed the openmpi: "openmpi-1.10.2.tar.bz2" > > But when I get to: > /parallel-bgl-0.7.0/build/cmake .. > > I can't find a good solution online to this cstddef.hpp error. > > Any suggestions? > > > My system: uname -a > > Linux atomix 4.2.0-16-generic #19-Ubuntu SMP Thu Oct 8 14:46:51 UTC 2015 i686 i686 i686 GNU/Linux

1 0

[proto] non-proto objects as terminals
by Igor R 30 May '16

30 May '16

I would like to use instances of a non-proto class as proto terminals for all purposes. To enable this functionality, I use is_terminal metafunction that I pass to BOOST_PROTO_DEFINE_OPERATORS(). This actually defines the operators, so the following expression makes an expression tree, as expected: non_proto_obj * proto_obj; However, I cannot do this: non_proto_obj = proto_obj; Or this: non_proto_obj[proto_obj]; While the opposite does compile: proto_obj = non_proto_obj; proto_obj[non_proto_obj]; How to solve this issue? Thanks! P.S.: here is an sscce: /////////////////// #include <iostream> #include <boost/proto/proto.hpp> #include <boost/mpl/int.hpp> namespace mpl = boost::mpl; namespace proto = boost::proto; using proto::_; template<typename Expr> struct my_expression; struct my_domain : proto::domain<proto::generator<my_expression> > {}; template<int I> struct placeholder {}; template<typename Expr> struct my_expression : proto::extends<Expr, my_expression<Expr>, my_domain> { explicit my_expression(Expr const &expr = Expr()) : my_expression::proto_extends(expr) {} BOOST_PROTO_EXTENDS_USING_ASSIGN(my_expression<Expr>) }; const my_expression<proto::terminal<placeholder<1>>::type> _1; namespace app { struct non_proto_type {}; template <typename T> struct is_terminal : mpl::false_ {}; template<> struct is_terminal<non_proto_type> : mpl::true_ {}; BOOST_PROTO_DEFINE_OPERATORS(is_terminal, my_domain) non_proto_type non_proto; } int main() { _1 = app::non_proto; // ok, builds temporary proto expression //app::non_proto = _1; // does not compile! no operator= _1[app::non_proto]; // ok //app::non_proto[_1]; // does not compile! no operator[] (+app::non_proto)[_1]; // ok! applying unary + to make a proto expression first, then operator[] is available }

1 0

Boost.Fiber mini-review May 23 - June 1
by Nat Goodspeed 30 May '16

30 May '16

Hi all, The Boost.Fiber candidate library by Oliver Kowalke begins a mini-review today, Monday May 23, which will close Wednesday June 1. It was last reviewed in September 2015; the verdict at that time was "not yet." Oliver has been working steadily to address review comments and to improve the library in other ways, and has brought the library back for mini-review. The updated documentation is here: http://olk.github.io/libs/fiber/doc/html/index.html The code is on the master branch of this repository: https://github.com/olk/boost-fiber/tree/master I believe it is Oliver's intention to respond to review feedback on the develop branch, leaving the master branch stable during the review. I will monitor reviews and discussion on both the boost-users@ list and the boost@ developers' list. Please include at least "fiber" and "review" in the subject line of your mail, e.g. by replying to this message. (Please reply to only ONE list, however.) I will also check the Boost Library Incubator for Fiber reviews: http://rrsd.com/blincubator.com/bi_library/fiber/?gform_post_id=859 though I check that less frequently than email. Please do remember to state in your review whether you think the library should be accepted as a Boost library. Thank you for your interest and your feedback! ----------------------------------------------------- Here follows a synopsis of issues raised during the September 2015 review: Cross-thread fiber migration: Evidently the community strongly desires the ability to transfer a suspended fiber from one thread to another. Now supported, with documentation. Cross-thread migration support implies a requirement to document the thread safety requirements of the customization API. Addressed. Standard required timing specifications: meet (30.2.4 Timing specifications [thread.req.timing]). Addressed. Adapt one or more existing test suites for thread facilities to validate the correctness of the Fiber library's synchronization constructs. The requester clarified in private mail that I misstated his suggestion: he wanted Oliver to review one or more such test suites to discover the kinds of issues that can arise with thread synchronization constructs. He has professed himself satisfied with the current state of the Fiber library's synchronization constructs. std::chrono support: ensure that wait_until() can accept any supported time_point specialization. Addressed. C++11 compatibility. Addressed. Document that this_fiber::yield() (et al.) are valid from main(), or in general from a thread function, as well as from explicitly-launched fibers. Addressed. Make shared_state lock requirements explicit: for example, make mark_ready_and_notify_() accept a std::unique_lock<>& (or &&) to force its caller to provide one. Addressed. Avoid holding mutex during condition_variable::notify_*() calls. Addressed. packaged_task must not decay-copy its task arguments. Addressed. Align fibers::async() signature, result description and invoke_helper implementation with std::async(). Avoid returning std::move(...). Addressed. Wait list implementation: try an intrusive linked list of fiber_context objects. Addressed. Avoid sleeping thread when no fibers are ready -- block on external event. Better handling of waiting tasks (decentralized wait queues?). Addressed. Optimization to resume awakened fiber on the thread that awakens it. Hooks provided. Template redundancy: eliminate duplication between specializations for T, T& and void. The future, shared_future, shared_state, promise and task_object templates were specifically cited. Addressed. Leverage predicate-based condition::wait() overload internally. Addressed. Nested schedulers: make schedulers be schedulable entities themselves. Not implemented. Improve robustness of `promise' handling in Asynchronous Callbacks documentation. Avoid overconfident remarks about it. Addressed. Fix Note overstating the requirements on condition_variable::wait(). Addressed.

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[test] how to test std::pair with BOOST_TEST
by Tan, Tom (Shanghai) 29 May '16

29 May '16

The following snippet does not compile with VS2015 and boost 1.61. What should the correct way to do it? Thanks. // compile with cl.exe /EHSc #define BOOST_TEST_MODULE pair #include <boost/test/included/unit_test.hpp> std::pair<uint32_t, uint32_t> v() { return std::make_pair(0, 0); } BOOST_AUTO_TEST_CASE(range) { BOOST_TEST(std::make_pair(0, 0) == v()); } Here's the error message: C:\3rd\boost_1_61_0\boost/test/tools/assertion.hpp(163): error C2678: binary '==': no operator found which takes a left-hand operand of type 'std::pair<int,int>' (or there is no acceptable conversion) C:\3rd\boost_1_61_0\boost/function/function_base.hpp(740): note: could be 'bool boost::operator ==(boost::detail::function::useless_clear_type *,const boost::function_base &)' C:\3rd\boost_1_61_0\boost/function/function_base.hpp(728): note: or 'bool boost::operator ==(const boost::function_base &,boost::detail::function::useless_clear_type *)' C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\exception(329): note: or 'bool std::operator ==(const std::exception_ptr &,const std::exception_ptr &) throw()' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\exception(334): note: or 'bool std::operator ==(std::nullptr_t,const std::exception_ptr &) throw()' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\exception(339): note: or 'bool std::operator ==(const std::exception_ptr &,std::nullptr_t) throw()' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\system_error(365): note: or 'bool std::operator ==(const std::error_code &,const std::error_code &) noexcept' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\system_error(373): note: or 'bool std::operator ==(const std::error_code &,const std::error_condition &) noexcept' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\system_error(381): note: or 'bool std::operator ==(const std::error_condition &,const std::error_code &) noexcept' [found using argument-dependent lookup] C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\system_error(389): note: or 'bool std::operator ==(const std::error_condition &,const std::error_condition &) noexcept' [found using argument-dependent lookup] C:\3rd\boost_1_61_0\boost/function/function_base.hpp(799): note: or 'bool boost::operator ==<T>(Functor,const boost::function_base &)' with [ T=std::pair<int,int>, Functor=std::pair<int,int> ] C:\3rd\boost_1_61_0\boost/function/function_base.hpp(790): note: or 'bool boost::operator ==<T>(const boost::function_base &,Functor)' with [ T=std::pair<uint32_t,uint32_t>, Functor=std::pair<uint32_t,uint32_t> ] C:\3rd\boost_1_61_0\boost/test/tools/assertion.hpp(163): note: while trying to match the argument list '(std::pair<int,int>, std::pair<uint32_t,uint32_t>)' C:\3rd\boost_1_61_0\boost/test/tools/assertion.hpp(326): note: see reference to class template instantiation 'boost::test_tools::assertion::op::EQ<ValType,T,void>' being compiled with [ ValType=std::pair<int,int>, T=std::pair<uint32_t,uint32_t> ] s.cpp(14): note: see reference to class template instantiation 'boost::test_tools::assertion::binary_expr<ExprType,std::pair<uint32_t,uint32_t>,boost::test_tools::assertion::op::EQ<ValType,T,void>>' being compiled with [ ExprType=boost::test_tools::assertion::value_expr<std::pair<int,int>>, ValType=std::pair<int,int>, T=std::pair<uint32_t,uint32_t> ] C:\3rd\boost_1_61_0\boost/test/tools/assertion.hpp(377): warning C4624: 'boost::test_tools::assertion::binary_expr<ExprType,std::pair<uint32_t,uint32_t>,boost::test_tools::assertion::op::EQ<ValType,T,void>>': destructor was implicitly defined as deleted with [ ExprType=boost::test_tools::assertion::value_expr<std::pair<int,int>>, ValType=std::pair<int,int>, T=std::pair<uint32_t,uint32_t> ]

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Call for Papers for Meeting C++ 2016 ends on Friday night!
by Jens Weller 25 May '16

25 May '16

Hello Boost Community! a short reminder, that the deadline is coming up for submitting your talk to this years Meeting C++ conference! Meeting C++ 2016 Page: http://meetingcpp.com/index.php/mcpp2016.html Talk submission page: https://meetingcpp.com/mcpp/submittalk/ thanks, Jens Weller

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