46 lines
933 B
C++
46 lines
933 B
C++
/*
|
|
Copyright 2018 T. Zachary Laine
|
|
(whatwasthataddress@gmail.com)
|
|
|
|
Distributed under Boost Software License, Version 1.0.
|
|
(See accompanying file LICENSE_1_0.txt or copy at
|
|
http://www.boost.org/LICENSE_1_0.txt)
|
|
*/
|
|
|
|
// MACRO: BOOST_NO_CXX17_IF_CONSTEXPR
|
|
// TITLE: C++17 if constexpr
|
|
// DESCRIPTION: C++17 if constexpr are not supported.
|
|
|
|
namespace boost_no_cxx17_if_constexpr {
|
|
|
|
template <typename T, typename U>
|
|
struct same
|
|
{
|
|
static constexpr bool value = false;
|
|
};
|
|
|
|
template <typename T>
|
|
struct same<T, T>
|
|
{
|
|
static constexpr bool value = true;
|
|
};
|
|
|
|
int test()
|
|
{
|
|
if constexpr (true) {
|
|
if constexpr (1 != 0) {
|
|
if constexpr (same<int, double>::value) {
|
|
static_assert(!same<int, double>::value, "");
|
|
return 1;
|
|
} else if constexpr (false) {
|
|
return 1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
}
|