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/*<-
Copyright (c) 2016 Barrett Adair
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
->*/
//[ apply_member_pointer
#include <type_traits>
#include <boost/callable_traits/apply_member_pointer.hpp>
namespace ct = boost::callable_traits;
struct foo;
struct bar;
int main() {
{
// function type -> member function pointer type
using f = int(int);
using g = ct::apply_member_pointer_t<f, foo>;
using expect = int(foo::*)(int);
static_assert(std::is_same<g, expect>::value, "");
}
{
// function pointer type (unqualified) -> member function pointer type
using f = int(*)();
using g = ct::apply_member_pointer_t<f, foo>;
using expect = int(foo::*)();
static_assert(std::is_same<g, expect>::value, "");
}
{
// function pointer type (qualified) -> member data pointer type
// Look out for cases like these two. If the input type to apply_member_pointer
// is a ``[*qualified]`` function pointer type, then the aliased type is a member data
// pointer to a ``[*qualified function pointer]``.
{
using f = int(*&)();
using g = ct::apply_member_pointer_t<f, foo>;
using expect = int (* foo::*)();
static_assert(std::is_same<g, expect>::value, "");
}
{
using f = int(* const)();
using g = ct::apply_member_pointer_t<f, foo>;
using expect = int (* const foo::*)();
static_assert(std::is_same<g, expect>::value, "");
}
}
{
// function reference type -> member function pointer type
using f = void(&)();
using g = ct::apply_member_pointer_t<f, foo>;
using expect = void(foo::*)();
static_assert(std::is_same<g, expect>::value, "");
}
{
// member function pointer type -> member function pointer type
// (note the different parent class)
using f = int(bar::*)() const;
using g = ct::apply_member_pointer_t<f, foo>;
using expect = int(foo::*)() const;
static_assert(std::is_same<g, expect>::value, "");
}
{
// non-callable type -> member data pointer type
using g = ct::apply_member_pointer_t<int, foo>;
using expect = int foo::*;
static_assert(std::is_same<g, expect>::value, "");
}
{
// function object type -> member data pointer type
// the same is true for lambdas and generic lambdas
auto lambda = [](){};
using f = decltype(lambda);
using g = ct::apply_member_pointer_t<f, foo>;
using expect = f foo::*;
static_assert(std::is_same<g, expect>::value, "");
}
}
//]
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