variant2/test/variant_holds_alternative_cx.cpp
2017-06-01 02:03:35 +03:00

44 lines
1.0 KiB
C++

// 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;
#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
int main()
{
{
constexpr variant<int> v;
STATIC_ASSERT( holds_alternative<int>( v ) );
}
{
constexpr variant<int, float> v;
STATIC_ASSERT( holds_alternative<int>( v ) );
STATIC_ASSERT( !holds_alternative<float>( v ) );
}
{
constexpr variant<int, float> v( 3.14f );
STATIC_ASSERT( !holds_alternative<int>( v ) );
STATIC_ASSERT( holds_alternative<float>( v ) );
}
{
constexpr variant<int, float, float> v;
STATIC_ASSERT( holds_alternative<int>( v ) );
}
{
constexpr variant<int, int, float> v( 3.14f );
STATIC_ASSERT( holds_alternative<float>( v ) );
}
}