• David Feuer's avatar
    Make unwords and words fuse somewhat · e73ab541
    David Feuer authored
    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
OldList.hs 41.5 KB