map is:exact -package:text -package:containers -package:base -package:dlist -package:Cabal-syntax -package:base-compat-batteries -package:insert-ordered-containers -package:filepath -package:dense-linear-algebra -package:conduit -package:amazonka-core -package:incipit-base package:basement
Map all element a from a block to a new block of b
Map all elements in a list