Example 9: Using CETL's variant

Full example for cetl::variant

#include "cetl/pf17/variant.hpp"
#include <string>
#include <algorithm>
#include <iostream>
#include <gtest/gtest.h>
 
TEST(example_09_variant, basic_usage)
{
cetl::pf17::variant<int, float> v, w;
v     = 42;  // v contains int
int i = cetl::pf17::get<int>(v);
EXPECT_EQ(42, i);
w = cetl::pf17::get<int>(v);
w = cetl::pf17::get<0>(v);  // same effect as the previous line
w = v;                      // same effect as the previous line
 
//  cetl::pf17::get<double>(v); // error: no double in [int, float]
//  cetl::pf17::get<3>(v);      // error: valid index values are 0 and 1
 
float* result = cetl::pf17::get_if<float>(&w);  // w contains int, not float: will return null NOLINT(*-use-auto)
std::cout << "get_if<float>(&w) => " << result << '\n';
 
using namespace std::literals;
 
cetl::pf17::variant<std::string> x("abc");
// converting constructors work when unambiguous
x = "def";  // converting assignment also works when unambiguous
 
cetl::pf17::variant<std::string, void const*> y("abc");
// casts to void const * when passed a char const *
EXPECT_TRUE(cetl::pf17::holds_alternative<void const*>(y));
y = "xyz"s;
EXPECT_TRUE(cetl::pf17::holds_alternative<std::string>(y));
}