Most idiomatic implementation of `[a -> a] -> (a -> a)`

Question

If I have a list of functions, each of the type a -> a for some type, what is the most shortest, elegant and idiomatic way to combine them; preferably withou

Answer 1

Another one, which may not be shorter than foldr (.) id but which I think is cute:

foo = flip (foldr id)

Answer 2

I'd say you're not going to beat

comp = foldr (.) id

Why? Well we have a list of things and we're trying to reduce it in a right associative way.

If you look at the implementations of and, sum, maximum and similar, you'll see that this is how they're implemented in the standard library, I don't think you get more idiomatic than that :)

Tangent: I hesitate to add the foldr1 variant mentioned in comments because I'd say that it's unexpected behavior for this to be partial, unlike say maximum where it clearly must be.