functional (function::function(F)): LWG 2132: Disable constructor if argument isn't callable.

* include/std/functional (function::function(F)): LWG 2132: Disable
	constructor if argument isn't callable.
	* testsuite/20_util/function/cons/callable.cc: New.

From-SVN: r186947
This commit is contained in:
Jonathan Wakely 2012-04-29 22:59:37 +00:00 committed by Jonathan Wakely
parent 112448b448
commit 143a1ce16c
3 changed files with 83 additions and 14 deletions

View File

@ -1,3 +1,9 @@
2012-04-29 Jonathan Wakely <jwakely.gcc@gmail.com>
* include/std/functional (function::function(F)): LWG 2132: Disable
constructor if argument isn't callable.
* testsuite/20_util/function/cons/callable.cc: New.
2012-04-29 Marc Glisse <marc.glisse@inria.fr>
PR libstdc++/22200

View File

@ -1856,7 +1856,7 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
{
typedef _Function_base::_Base_manager<_Functor*> _Base;
public:
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
@ -1994,7 +1994,7 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
typedef _Simple_type_wrapper<_Functor> _Wrapper;
typedef _Function_base::_Base_manager<_Wrapper> _Base;
public:
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
@ -2038,7 +2038,23 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
{
typedef _Res _Signature_type(_ArgTypes...);
struct _Useless { };
template<typename _Functor>
using _Invoke = decltype(__callable_functor(std::declval<_Functor&>())
(std::declval<_ArgTypes>()...) );
template<typename _CallRes, typename _Res1>
struct _CheckResult
: is_convertible<_CallRes, _Res1> { };
template<typename _CallRes>
struct _CheckResult<_CallRes, void>
: true_type { };
template<typename _Functor>
using _Callable = _CheckResult<_Invoke<_Functor>, _Res>;
template<typename _Cond, typename _Tp>
using _Requires = typename enable_if<_Cond::value, _Tp>::type;
public:
typedef _Res result_type;
@ -2099,11 +2115,9 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
* If @a __f is a non-NULL function pointer or an object of type @c
* reference_wrapper<F>, this function will not throw.
*/
template<typename _Functor>
function(_Functor __f,
typename enable_if<
!is_integral<_Functor>::value, _Useless>::type
= _Useless());
template<typename _Functor,
typename = _Requires<_Callable<_Functor>, void>>
function(_Functor);
/**
* @brief %Function assignment operator.
@ -2178,7 +2192,7 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
* reference_wrapper<F>, this function will not throw.
*/
template<typename _Functor>
typename enable_if<!is_integral<_Functor>::value, function&>::type
_Requires<_Callable<_Functor>, function&>
operator=(_Functor&& __f)
{
function(std::forward<_Functor>(__f)).swap(*this);
@ -2187,7 +2201,7 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
/// @overload
template<typename _Functor>
typename enable_if<!is_integral<_Functor>::value, function&>::type
function&
operator=(reference_wrapper<_Functor> __f) noexcept
{
function(__f).swap(*this);
@ -2294,11 +2308,9 @@ _GLIBCXX_HAS_NESTED_TYPE(result_type)
}
template<typename _Res, typename... _ArgTypes>
template<typename _Functor>
template<typename _Functor, typename>
function<_Res(_ArgTypes...)>::
function(_Functor __f,
typename enable_if<
!is_integral<_Functor>::value, _Useless>::type)
function(_Functor __f)
: _Function_base()
{
typedef _Function_handler<_Signature_type, _Functor> _My_handler;

View File

@ -0,0 +1,51 @@
// { dg-options "-std=gnu++0x" }
// { dg-do compile }
// Copyright (C) 2012 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
#include <functional>
#include <testsuite_hooks.h>
void* f(std::function<void()>) { return nullptr; }
int f(std::function<void(int)>) { return 1; }
void test01()
{
void* p __attribute__((unused));
int i __attribute__((unused));
p = f([] { });
i = f([] (int) { });
}
void g(std::function<void()>) { }
void h(std::function<int(int)>) { }
void test02()
{
g([] { return "ignored"; });
h([] (char c) { return c; });
}
int main()
{
test01();
test02();
return 0;
}