map -package:containers is:exact -package:base-compat -package:foldl -package:blaze-html -package:insert-ordered-containers -package:case-insensitive -package:incipit-base -package:hedgehog -package:base-prelude -package:conduit -package:ghc package:basement
Map all element a from a block to a new block of b
Map all elements in a list