Sections

Sections allow partial infix operators to be applied.

On the right:

(Ⓧ y) = \x -> x Ⓧ y

On the left:

(y Ⓧ) = \x -> y Ⓧ x

Examples:

doble = (* 2)         -- == (2 *)
doble 5
10

map (* 2) [1, 2, 3]   -- better than (\x -> x * 2) [1, 2, 3]
[2, 4, 6]

half = (/ 2)          -- != (2 /)
half 6
3

isUppercase = (`elem` ['A' .. 'Z'])
isUppercase 'c'
False