[Haskell-cafe] Precedence (Part 2)

Hi folks

let f = sum.map (^2).filter even f [1..4] 20

So far so good!

sum.map (^2).filter even [1..4] returns an error.

How is it that the composition above as part of a function equation doesn't return any errors while on its own it requires parentheses? I can understand the need for the parentheses - the composition operator takes two arguments/operand,s each of which is a mapping which must correspond to specific domain and range requirements i.e. (b->c -> (a->b) -> (a->c) Why aren't the parentheses required in the function definition? Cheers, Paul