#9538: unwords does not participate in list fusion -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- I'm not quite sure how far this can go, but `unwords` should almost certainly be a good consumer or a good consumer. Currently it is neither. Making it a good consumer is trivial, given `concatMap` that fuses: {{{#!hs unwords = tail . concatMap (' ':) }}} Alternatively, we should be able to make it a good producer without too much trouble, I think. I have my doubts about making it both. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9538 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler