overload pattern Example
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#include <iostream>
#include <variant>
template<class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
template<class... Ts> overloaded(Ts...) -> overloaded<Ts...>;
int main()
{
auto PrintVisitor = [](const auto& t) { std::cout << t << '\n'; };
std::variant<int, float, std::string> intFloatString { "Hello" };
std::visit(overloaded{
[](int& i) { i*= 2; },
[](float& f) { f*= 2.0f; },
[](std::string& s) { s = s + s; }
}, intFloatString);
std::visit(PrintVisitor, intFloatString);
// "custom" print:
std::visit(overloaded{
[](const int& i) { std::cout << "int: " << i << '\n'; },
[](const float& f) { std::cout << "float: " << f << '\n'; },
[](const std::string& s) { std::cout << "string: " << s << '\n';}
}, intFloatString);
return 0;
}
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