map -package:containers -package:Cabal-syntax -is:exact -package:foldl -package:invertible -package:insert-ordered-containers -package:dense-linear-algebra -package:incipit-base -package:case-insensitive is:exact -package:monoidal-containers -package:charset package:basement
Map all element a from a block to a new block of b
Map all elements in a list