#13905: ApplicativeDo is too strict with newtype patterns -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The fix to #13875 went a little too far, and interprets newtype constructor patterns as strict. It's not clear to me how to fix this, as the `Name` of the constructor doesn't seem to give any clue as to whether it is a newtype constructor or a data constructor. The comment at the top of `basicTypes/Name.hs` indicates {{{ -- * 'Name.Name' is the type of names that have had their scoping and binding resolved. They -- have an 'OccName.OccName' but also a 'Unique.Unique' that disambiguates Names that have -- the same 'OccName.OccName' and indeed is used for all 'Name.Name' comparison. Names -- also contain information about where they originated from, see "Name#name_sorts" }}} which suggests that this information should be available, but I don't know what's involved in propagating it to the right place. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13905 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler