And the poor man's list, and the poor man's parser, and the poor man's state.

We need a poor man's interface to generalise them, as well as suitable poor man's laws to abide by, and pretty soon we'll have some sweet poor man's code re-use!

Is early return poor man's monad?

(Nod to https://stackoverflow.com/questions/2497801/closures-are-poo... yet real question.)