I found this code on cppreference.com. I was wondering if Boost provides a similar function for its variant type. I found the Boost documentation really awful and can't find anything.
int main()
{
std::variant<int, std::string> v = "abc";
std::cout << std::boolalpha
<< "variant holds int? "
<< std::holds_alternative<int>(v) << '\n'
<< "variant holds string? "
<< std::holds_alternative<std::string>(v) << '\n';
}
No but, you can use the type()
method:
#include <iostream>
#include <boost/variant.hpp>
int main()
{
boost::variant<int, std::string> v = "abc";
std::cout << std::boolalpha
<< "variant holds int? "
<< (v.type() == typeid(int)) << '\n'
<< "variant holds string? "
<< (v.type() == typeid(std::string)) << '\n';
}
But it will not protect you against having the same type twice (boost::variant<int, int, std::string>
) as std::holds_alternative would do.