When You Should Use Lists in Haskell (Mostly, You Should Not) J. Waldmann, March 9, 2017. Introduction It seems that the designers of the programming language Haskell were madly in love with singly linked lists. They even granted notational privileges: e.g., the data constructor for a non-empty list (“cons”) uses just one letter (:) Looking at the Haskell standard, it also seems that singly linked