title: List Comprehensions
List comprehensions are a powerful tool in haskell for working with sets.
someNumbers :: [Int] # a list of integers containing, 1, 2 and 3 someNumbers = [1,2,3] allLower :: [Char] allLower = [toLower c | c <- "Hello, World!" ] parity :: [(Int, Boolean)] parity = [ ( x , even x ) | x <- [1,2,3] ]
Parity produces the following set:
[ (1, False), (2, True), (3, False) ]
The right hand side of the list comprehension is composed of two parts; a generator and guards.