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// MPark.Variant
//
// Copyright Michael Park, 2015-2017
//
// 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 <mpark/variant.hpp>
#include <iostream>
#include <string>
#include <gtest/gtest.h>
TEST(Variant, Intro) {
// direct initialization.
mpark::variant<int, std::string> v("hello world!");
// direct access via reference.
EXPECT_EQ("hello world!", mpark::get<std::string>(v));
// bad access.
#ifdef MPARK_EXCEPTIONS
EXPECT_THROW(mpark::get<int>(v), mpark::bad_variant_access);
#endif
// copy construction.
mpark::variant<int, std::string> w(v);
// direct access via pointer.
EXPECT_FALSE(mpark::get_if<int>(&w));
EXPECT_TRUE(mpark::get_if<std::string>(&w));
// diff-type assignment.
v = 42;
struct unary {
int operator()(int) const noexcept { return 0; }
int operator()(const std::string &) const noexcept { return 1; }
}; // unary
// single visitation.
EXPECT_EQ(0, mpark::visit(unary{}, v));
// same-type assignment.
w = "hello";
EXPECT_NE(v, w);
// make `w` equal to `v`.
w = 42;
EXPECT_EQ(v, w);
struct binary {
int operator()(int, int) const noexcept { return 0; }
int operator()(int, const std::string &) const noexcept { return 1; }
int operator()(const std::string &, int) const noexcept { return 2; }
int operator()(const std::string &, const std::string &) const noexcept {
return 3;
}
}; // binary
// binary visitation.
EXPECT_EQ(0, mpark::visit(binary{}, v, w));
}
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