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#include <cstdio>
#include <string>
#include <variant>
#include <vector>
struct S {
operator int() { throw 42; }
};
int main() {
bool has_variant = true;
printf("%d\n", has_variant); // break here
std::variant<int, double, char> v1;
std::variant<int, double, char> &v1_ref = v1;
std::variant<int, double, char> v2;
std::variant<int, double, char> v3;
std::variant<std::variant<int, double, char>> v_v1;
std::variant<int, double, char> v_no_value;
// The next variant has many types, meaning the type index does not fit in
// a byte and must be `unsigned short` instead of `unsigned char` when
// using the unstable libc++ ABI. With stable libc++ ABI, the type index
// is always just `unsigned int`.
std::variant<
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int, int, int, int,
int, int, int, int, int, int, int, int, int, int, int, int>
v_many_types_no_value;
v1 = 12; // v contains int
v_v1 = v1;
int i = std::get<int>(v1);
printf("%d\n", i); // break here
v2 = 2.0;
double d = std::get<double>(v2);
printf("%f\n", d);
v3 = 'A';
char c = std::get<char>(v3);
printf("%d\n", c);
// Checking v1 above and here to make sure we done maintain the incorrect
// state when we change its value.
v1 = 2.0;
d = std::get<double>(v1);
printf("%f\n", d); // break here
try {
v_no_value.emplace<0>(S());
} catch (...) {
}
printf("%zu\n", v_no_value.index());
try {
v_many_types_no_value.emplace<0>(S());
} catch (...) {
}
printf("%zu\n", v_many_types_no_value.index());
return 0; // break here
}
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