map -package:containers -package:insert-ordered-containers -package:Cabal-syntax -package:ghc -package:base-prelude -package:blaze-html -package:monoidal-containers -package:dense-linear-algebra -package:base-compat-batteries -package:conduit -is:exact package:basement is:exact
Map all element a from a block to a new block of b
Map all elements in a list