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fusion fold and transform passing refs for lvalues as per result_of protocol

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[SVN r38039]
This commit is contained in:
Dan Marsden
2007-06-19 21:30:06 +00:00
parent 0e5cb04b99
commit 09a6da1f80
13 changed files with 157 additions and 40 deletions
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10
include/boost/fusion/algorithm/iteration/detail/fold.hpp
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@ -13,6 +13,9 @@
#include <boost/fusion/iterator/distance.hpp>
#include <boost/utility/result_of.hpp>
#include <boost/type_traits/add_const.hpp>
#include <boost/type_traits/add_reference.hpp>
namespace boost { namespace fusion {
namespace result_of
{
@ -32,8 +35,11 @@ namespace detail
template <typename Iterator, typename State, typename F>
struct fold_apply
: boost::result_of<F(typename result_of::value_of<Iterator>::type, State)>
{};
{
typedef typename result_of::deref<Iterator>::type dereferenced;
typedef typename add_reference<typename add_const<State>::type>::type lvalue_state;
typedef typename boost::result_of<F(dereferenced, lvalue_state)>::type type;
};
template <typename First, typename Last, typename State, typename F>
struct static_fold;

6
include/boost/fusion/algorithm/transformation/detail/replace.hpp
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@ -9,6 +9,7 @@
#include <boost/type_traits/is_convertible.hpp>
#include <boost/mpl/if.hpp>
#include <boost/type_traits/remove_reference.hpp>
namespace boost { namespace fusion { namespace detail
{
@ -43,14 +44,15 @@ namespace boost { namespace fusion { namespace detail
replacer(T const& old_value, T const& new_value)
: old_value(old_value), new_value(new_value) {}
template<typename Params>
template<typename Sig>
struct result;
template <typename U1, typename U2>
struct result<replacer<U1>(U2)>
{
typedef typename remove_reference<U2>::type value;
typedef typename
mpl::if_<is_convertible<T, U2>, U2, U2 const&>::type
mpl::if_<is_convertible<T, value>, value, value const&>::type
type;
};

4
include/boost/fusion/algorithm/transformation/detail/replace_if.hpp
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@ -9,6 +9,7 @@
#include <boost/utility/enable_if.hpp>
#include <boost/mpl/if.hpp>
#include <boost/type_traits/remove_reference.hpp>
namespace boost { namespace fusion { namespace detail
{
@ -49,8 +50,9 @@ namespace boost { namespace fusion { namespace detail
template <typename F1, typename T1, typename U>
struct result<replacer_if<F1, T1>(U)>
{
typedef typename remove_reference<U>::type value;
typedef typename
mpl::if_<is_convertible<T, U>, U, U const&>::type
mpl::if_<is_convertible<T, value>, value, value const&>::type
type;
};

6
include/boost/fusion/sequence/view/transform_view/detail/deref_impl.hpp
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@ -30,7 +30,7 @@ namespace boost { namespace fusion
struct apply
{
typedef typename
result_of::value_of<typename Iterator::first_type>::type
result_of::deref<typename Iterator::first_type>::type
value_type;
typedef detail::apply_transform_result<typename Iterator::transform_type> transform_type;
@ -52,10 +52,10 @@ namespace boost { namespace fusion
struct apply
{
typedef typename
result_of::value_of<typename Iterator::first1_type>::type
result_of::deref<typename Iterator::first1_type>::type
value1_type;
typedef typename
result_of::value_of<typename Iterator::first2_type>::type
result_of::deref<typename Iterator::first2_type>::type
value2_type;
typedef detail::apply_transform_result<typename Iterator::transform_type> transform_type;

9
include/boost/fusion/sequence/view/zip_view/detail/advance_impl.hpp
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@ -11,6 +11,7 @@
#include <boost/fusion/sequence/view/zip_view/zip_view_iterator_fwd.hpp>
#include <boost/fusion/iterator/advance.hpp>
#include <boost/fusion/algorithm/transformation/transform.hpp>
#include <boost/type_traits/remove_reference.hpp>
namespace boost { namespace fusion {
@ -21,13 +22,15 @@ namespace boost { namespace fusion {
template<typename N>
struct poly_advance
{
template<typename T>
template<typename Sig>
struct result;
template<typename N1, typename It>
struct result<poly_advance<N1>(It)>
: result_of::advance<It,N>
{};
{
typedef typename remove_reference<It>::type it;
typedef typename result_of::advance<it,N>::type type;
};
template<typename It>
typename result<poly_advance(It)>::type

14
include/boost/fusion/sequence/view/zip_view/detail/deref_impl.hpp
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@ -16,6 +16,8 @@
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/remove_const.hpp>
namespace boost { namespace fusion {
@ -25,15 +27,19 @@ namespace boost { namespace fusion {
{
struct poly_deref
{
template<typename T>
template<typename Sig>
struct result;
template<typename It>
struct result<poly_deref(It)>
: mpl::eval_if<is_same<It, unused_type>,
{
typedef typename remove_const<
typename remove_reference<It>::type>::type it;
typedef typename mpl::eval_if<is_same<it, unused_type>,
mpl::identity<unused_type>,
result_of::deref<It> >
{};
result_of::deref<it> >::type type;
};
template<typename It>
typename result<poly_deref(It)>::type

14
include/boost/fusion/sequence/view/zip_view/detail/next_impl.hpp
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@ -15,6 +15,8 @@
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/remove_const.hpp>
namespace boost { namespace fusion {
@ -24,15 +26,19 @@ namespace boost { namespace fusion {
{
struct poly_next
{
template<typename T>
template<typename Sig>
struct result;
template<typename It>
struct result<poly_next(It)>
: mpl::eval_if<is_same<It, unused_type>,
{
typedef typename remove_const<
typename remove_reference<It>::type>::type it;
typedef typename mpl::eval_if<is_same<it, unused_type>,
mpl::identity<unused_type>,
result_of::next<It> >
{};
result_of::next<it> >::type type;
};
template<typename It>
typename result<poly_next(It)>::type

13
include/boost/fusion/sequence/view/zip_view/detail/prior_impl.hpp
View File

@ -15,6 +15,8 @@
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/remove_const.hpp>
namespace boost { namespace fusion {
@ -24,15 +26,18 @@ namespace boost { namespace fusion {
{
struct poly_prior
{
template<typename T>
template<typename Sig>
struct result;
template<typename It>
struct result<poly_prior(It)>
: mpl::eval_if<is_same<It, unused_type>,
{
typedef typename remove_const<
typename remove_reference<It>::type>::type it;
typedef typename mpl::eval_if<is_same<it, unused_type>,
mpl::identity<unused_type>,
result_of::prior<It> >
{};
result_of::prior<it> >::type type;
};
template<typename It>
typename result<poly_prior(It)>::type

10
include/boost/fusion/sequence/view/zip_view/detail/strictest_traversal.hpp
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@ -39,15 +39,17 @@ namespace boost { namespace fusion {
struct strictest_traversal_impl
{
template<typename T>
template<typename Sig>
struct result;
template<typename Next, typename StrictestSoFar>
struct result<strictest_traversal_impl(Next, StrictestSoFar)>
{
typedef StrictestSoFar tag1;
typedef typename traits::category_of<
typename remove_reference<Next>::type>::type tag2;
typedef typename remove_reference<Next>::type next_value;
typedef typename remove_reference<StrictestSoFar>::type strictest_so_far;
typedef strictest_so_far tag1;
typedef typename traits::category_of<next_value>::type tag2;
typedef typename stricter_traversal<tag1,tag2>::type type;
};

7
include/boost/fusion/sequence/view/zip_view/zip_view.hpp
View File

@ -73,8 +73,11 @@ namespace boost { namespace fusion {
template<typename Lhs, typename Rhs>
struct result<poly_min(Lhs, Rhs)>
: mpl::min<Lhs, Rhs>
{};
{
typedef typename remove_reference<Lhs>::type lhs;
typedef typename remove_reference<Rhs>::type rhs;
typedef typename mpl::min<lhs, rhs>::type type;
};
};
template<typename Sequences>

1
test/Jamfile
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@ -145,4 +145,3 @@ import testing ;
run sequence/ext_/iterator_range_s.cpp ;
explicit iterator_range_s ;
}

42
test/algorithm/fold.cpp
View File

@ -19,6 +19,10 @@
#include <boost/mpl/int.hpp>
#include <boost/mpl/vector.hpp>
#include <boost/type_traits/remove_const.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/is_reference.hpp>
#include <string>
using boost::mpl::if_;
@ -33,7 +37,8 @@ struct add_ints_only
template <typename T, typename State>
struct result<add_ints_only(T,State)>
{
typedef State type;
typedef typename boost::remove_const<
typename boost::remove_reference<State>::type>::type type;
};
template <typename T, typename State>
@ -58,11 +63,16 @@ struct count_ints
template <typename T, typename CountT>
struct result<count_ints(T,CountT)>
{
typedef typename boost::remove_const<
typename boost::remove_reference<T>::type>::type elem;
typedef typename boost::remove_const<
typename boost::remove_reference<CountT>::type>::type state;
typedef typename
if_<
is_same<T, int>
, typename boost::mpl::next<CountT>::type
, CountT
is_same<elem, int>
, typename boost::mpl::next<state>::type
, state
>::type
type;
};
@ -86,6 +96,25 @@ struct appender
}
};
struct lvalue_adder
{
template<typename Sig>
struct result;
template<typename T0, typename T1>
struct result<lvalue_adder(T0&, T1)>
{
// Second argument still needs to support rvalues - see definition of fusion::fold
typedef T0 type;
};
template<typename T0, typename T1>
T0 operator()(T0& lhs, T1 const& rhs) const
{
return lhs + rhs;
}
};
int
main()
{
@ -130,6 +159,11 @@ main()
== "abcde");
}
{
vector<int, int> vec(1,2);
BOOST_TEST(fusion::fold(vec, 0, lvalue_adder()) == 3);
}
{
typedef vector<int, char, int, double> vector_type;
vector_type v(12345, 'x', 678910, 3.36);

55
test/algorithm/transform.cpp
View File

@ -19,13 +19,12 @@
struct square
{
template<typename T>
template<typename Sig>
struct result;
template <typename T>
struct result<square(T)>
{
BOOST_STATIC_ASSERT(!boost::is_reference<T>::value);
typedef int type;
};
@ -38,7 +37,7 @@ struct square
struct add
{
template<typename T>
template<typename Sig>
struct result;
template <typename A, typename B>
@ -54,6 +53,42 @@ struct add
}
};
struct unary_lvalue_transform
{
template<typename Sig>
struct result;
template<typename T>
struct result<unary_lvalue_transform(T&)>
{
typedef T* type;
};
template<typename T>
T* operator()(T& t) const
{
return &t;
}
};
struct binary_lvalue_transform
{
template<typename Sig>
struct result;
template<typename T0, typename T1>
struct result<binary_lvalue_transform(T0&,T1&)>
{
typedef T0* type;
};
template<typename T0, typename T1>
T0* operator()(T0& t0, T1&) const
{
return &t0;
}
};
int
main()
{
@ -92,6 +127,20 @@ main()
BOOST_TEST((transform(tup1, tup2, add()) == make_vector(5, 7, 9)));
}
{
// Unary transform that requires lvalues, just check compilation
vector<int, int, int> tup1(1, 2, 3);
BOOST_TEST(at_c<0>(transform(tup1, unary_lvalue_transform())) == &at_c<0>(tup1));
BOOST_TEST(*begin(transform(tup1, unary_lvalue_transform())) == &at_c<0>(tup1));
}
{
vector<int, int, int> tup1(1, 2, 3);
vector<int, int, int> tup2(4, 5, 6);
BOOST_TEST(at_c<0>(transform(tup1, tup2, binary_lvalue_transform())) == &at_c<0>(tup1));
BOOST_TEST(*begin(transform(tup1, tup2, binary_lvalue_transform())) == &at_c<0>(tup1));
}
return boost::report_errors();
}