#9355: scanr does not participate in stream fusion -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.8.4 Component: | Version: 7.8.3 libraries/base | Keywords: Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Moderate (less Unknown/Multiple | than a day) Type of failure: Runtime | Blocked By: performance bug | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by dfeuer): Since `foldr` is strict in its list argument, I think it's then safe to go back to the pattern match style: {{{#!hs scanr f q0 = foldr go [q0] xs where go x qs@(q:_) = f x q : qs }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9355#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler