What is “point free” style (in Functional Programming)?

Question

A phrase that I\'ve noticed recently is the concept of \"point free\" style...

First, there was this question, and also this one.

Then, I discovered here the

Answer 1

Just look at the Wikipedia article to get your definition:

Tacit programming (point-free programming) is a programming paradigm in which a function definition does not include information regarding its arguments, using combinators and function composition [...] instead of variables.

Haskell example:

Conventional (you specify the arguments explicitly):

sum (x:xs) = x + (sum xs)
sum [] = 0

Point-free (sum doesn't have any explicit arguments - it's just a fold with + starting with 0):

 sum = foldr (+) 0

Or even simpler: Instead of g(x) = f(x), you could just write g = f.

So yes: It's closely related to currying (or operations like function composition).