map is:exact -package:text -package:dlist -package:amazonka-core -package:Cabal-syntax -package:aeson -package:incipit-base -package:base-compat-batteries -package:dense-linear-algebra -package:conduit -package:imports -package:blaze-html -package:bytestring package:basement
Map all element a from a block to a new block of b
Map all elements in a list