#15263: Fuse zipWith3 -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- I was surprised to discover that `zipWith3` has no `RULES` associated with it to aid fusion. Can we add these? I have no idea what I'm doing, but would this substitution work: {{{ {-# RULES "zipWith3" zipWith3 f a b c = zipWith id (zipWith f a b) c #-} }}} Those who know what they're doing will likely devise a better strategy. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15263 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler