map -package:containers -package:insert-ordered-containers -package:blaze-html -package:imports -is:exact -package:monoidal-containers -package:base-prelude -is:exact -package:Cabal-syntax -package:incipit-base -package:hedgehog -package:base-compat is:exact package:basement
Map all element a from a block to a new block of b
Map all elements in a list