match — Boost.HigherOrderFunctions 0.6 documentation

# match

## Header

    #include <boost/hof/match.hpp>

## Description

The `match` function adaptor combines several functions together and resolves which one should be called by using C++ overload resolution. This is different than the `first_of` adaptor which resolves them based on order.

## Synopsis

    template<class... Fs>
    constexpr match_adaptor<Fs...> match(Fs...fs);

## Requirements

Fs must be:

- ConstInvocable
- MoveConstructible

## Example

    #include <boost/hof.hpp>
    using namespace boost::hof;

    struct int_class
    {
        int operator()(int) const
        {
            return 1;
        }
    };

    struct foo
    {};

    struct foo_class
    {
        foo operator()(foo) const
        {
            return foo();
        }
    };

    typedef match_adaptor<int_class, foo_class> fun;

    static_assert(std::is_same<int, decltype(fun()(1))>::value, "Failed match");
    static_assert(std::is_same<foo, decltype(fun()(foo()))>::value, "Failed match");

    int main() {}

## References

- POO51 - Proposal for C++ Proposal for C++ generic overload function