map -package:containers is:exact -package:conduit -package:amazonka-core -package:incipit-base -package:charset -package:base-compat-batteries -package:insert-ordered-containers -package:base-compat -package:base-prelude -package:case-insensitive -package:bytestring package:basement
Map all element a from a block to a new block of b
Map all elements in a list