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// Copyright 2017 Peter Dimov.
//
// Distributed under the Boost Software License, Version 1.0.
//
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
#include <boost/variant2/variant.hpp>
using namespace boost::variant2;
struct X
{
int v;
X() = default;
constexpr X( int v ): v( v ) {}
constexpr operator int() const { return v; }
};
struct Y
{
int v;
constexpr Y(): v() {}
constexpr Y( int v ): v( v ) {}
constexpr operator int() const { return v; }
};
enum E
{
v
};
#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
template<class V, class T, class A> constexpr T test( A const& a )
{
V v;
v = a;
return get<T>(v);
}
int main()
{
{
constexpr variant<int> v( 1 );
constexpr auto w = test<variant<int>, int>( v );
STATIC_ASSERT( w == 1 );
}
{
constexpr variant<X> v( 1 );
constexpr auto w = test<variant<X>, X>( v );
STATIC_ASSERT( w == 1 );
}
#if defined( BOOST_LIBSTDCXX_VERSION ) && BOOST_LIBSTDCXX_VERSION < 50000
#else
{
constexpr variant<Y> v( 1 );
constexpr auto w = test<variant<Y>, Y>( v );
STATIC_ASSERT( w == 1 );
}
#endif
{
constexpr variant<int, float> v( 1 );
constexpr auto w = test<variant<int, float>, int>( v );
STATIC_ASSERT( w == 1 );
}
{
constexpr variant<int, float> v( 3.0f );
constexpr auto w = test<variant<int, float>, float>( v );
STATIC_ASSERT( w == 3.0f );
}
{
constexpr variant<int, int, float> v( 3.0f );
constexpr auto w = test<variant<int, int, float>, float>( v );
STATIC_ASSERT( w == 3.0f );
}
{
constexpr variant<E, E, X> v( 1 );
constexpr auto w = test<variant<E, E, X>, X>( v );
STATIC_ASSERT( w == 1 );
}
{
constexpr variant<int, int, float, float, X> v( X(1) );
constexpr auto w = test<variant<int, int, float, float, X>, X>( v );
STATIC_ASSERT( w == 1 );
}
#if defined( BOOST_LIBSTDCXX_VERSION ) && BOOST_LIBSTDCXX_VERSION < 50000
#else
{
constexpr variant<E, E, Y> v( 1 );
constexpr auto w = test<variant<E, E, Y>, Y>( v );
STATIC_ASSERT( w == 1 );
}
{
constexpr variant<int, int, float, float, Y> v( Y(1) );
constexpr auto w = test<variant<int, int, float, float, Y>, Y>( v );
STATIC_ASSERT( w == 1 );
}
#endif
}
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