get_or()

template<std::size_t I, typename T, typename V>

decltype(auto) kumi::function::get_or ( T && t, V && v )

inlinenodiscardconstexpr

#include <kumi/functional/monadic.hpp>

If T is a kumi::product_type, returns it's Ith element, returns an instance of V otherwise.

Note

Does not participate in overload resolution if I is not in [0, sizeof...(Ts)).

Template Parameters

I	Compile-time index of the element to access

Parameters

t	type to inspect
v	fallback value

Returns

A reference to the selected element of t if t is a kumi::product_type, the parameter v otherwise.