However, function objects, sometimes referred to as Niebloids, after Eric Niebler who pioneered their use in the Ranges library, are still few and rarely composable. With function objects we can send functions, and even complete overload sets, as arguments to other functions, return them, and combine them.

I will show you compositions I want, how to write them and with
gradual scope creep end up with a very powerful set of utilities that are easy to use and require surprisingly little code when using recent additions to the C++ language.