map is:exact -package:text -package:Cabal-syntax -package:charset -package:containers -package:conduit -package:incipit-base -package:monoidal-containers -package:integration -package:bytestring -package:base-compat-batteries -package:aeson -package:base-compat package:basement
Map all element a from a block to a new block of b
Map all elements in a list