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// Copyright Louis Dionne 2013-2017
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
#include <boost/hana/assert.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/type.hpp>
namespace hana = boost::hana;
using Function = void();
void function() { }
int main() {
{
struct T { };
T t;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(T{}),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(t),
hana::type_c<T>
));
}
// [cv-qualified] reference types
{
struct T { };
T t;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T&>(t)),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T const&>(t)),
hana::type_c<T const>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T volatile&>(t)),
hana::type_c<T volatile>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T const volatile&>(t)),
hana::type_c<T const volatile>
));
}
// [cv-qualified] rvalue reference types
{
struct T { };
T t;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T&&>(t)),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T const &&>(t)),
hana::type_c<T const>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T volatile&&>(t)),
hana::type_c<T volatile>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(static_cast<T const volatile&&>(t)),
hana::type_c<T const volatile>
));
}
// decltype_(type_c<T>) is the identity function
{
struct T;
auto const type_const = hana::type_c<T>;
auto const& type_const_ref = hana::type_c<T>;
auto& type_ref = hana::type_c<T>;
auto&& type_ref_ref = static_cast<decltype(type_ref)&&>(type_ref);
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(hana::type_c<T>),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(type_const),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(type_const_ref),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(type_ref),
hana::type_c<T>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(type_ref_ref),
hana::type_c<T>
));
}
// make sure we don't read from non-constexpr variables
{
struct T;
auto t = hana::type_c<T>;
auto x = 1;
constexpr auto r1 = hana::decltype_(t); (void)r1;
constexpr auto r2 = hana::decltype_(x); (void)r2;
}
// decltype_ with builtin arrays, function pointers and other weirdos
{
struct T { };
using A = T[3];
A a;
A& a_ref = a;
A const& a_const_ref = a;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(a),
hana::type_c<A>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(a_ref),
hana::type_c<A>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(a_const_ref),
hana::type_c<A const>
));
}
{
using Fptr = int(*)();
Fptr f;
Fptr& f_ref = f;
Fptr const& f_const_ref = f;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(f),
hana::type_c<Fptr>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(f_ref),
hana::type_c<Fptr>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(f_const_ref),
hana::type_c<Fptr const>
));
}
{
Function& function_ref = function;
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(function),
hana::type_c<Function>
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::decltype_(function_ref),
hana::type_c<Function>
));
}
}
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