xieite::memoize()

Defined in header <xieite/fn/memoize.hpp>

Memoizes a function call to immediately return its result when called with the same arguments again. This can be used to avoid repeating expensive calculations.


Declaration

 
template<typename F, typename... Args>
requires(std::invocable<F, Args...>)
std::invoke_result_t<F, Args...> memoize(F fn, const Args&... args)
noexcept(std::is_nothrow_invocable_v<F, Args...>);


Example

 
int add(int x, int y) {
	std::println("`add({}, {})` called", x, y);
	return x + y;
}

int main() {
	std::println("{}", xieite::memoize(add, 1, 2));
	std::println("{}", xieite::memoize(add, 1, 2)); // `add(1, 2)` is not called again
}
Output: 
`add(1, 2)` called
3
3
[View in Compiler Explorer]