-
Make `words` a good producer and `unwords` a good consumer for list fusion. Thus `unwords . words` will avoid producing an intermediate list of words, although it will produce each individual word. Make `unwords` slightly lazier, so that `unwords (s : undefined) = s ++ undefined` instead of `= undefined`. Reviewed By: austin Differential Revision: https://phabricator.haskell.org/D375
e73ab541