#9889: Pattern synonym does not work in top-level pattern bind -------------------------------------+------------------------------------- Reporter: goldfire | Owner: cactus Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.9 (Type checker) | Keywords: PatternSynonyms Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: GHC | Related Tickets: rejects valid program | Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Changes (by cactus): * failure: None/Unknown => GHC rejects valid program * component: Compiler => Compiler (Type checker) Old description:

When I say

{{{ pattern Id x = x

Id x = True }}}

I get

{{{ Not in scope: data constructor ‘Id’ }}}

This happens with both 7.8.3 and HEAD.

New description: When I say {{{ {-# LANGUAGE PatternSynonyms #-} pattern Id x = x Id x = True }}} I get {{{ Not in scope: data constructor ‘Id’ }}} This happens with both 7.8.3 and HEAD. -- Comment: Note that pattern binds, in general, don't have this problem, only at the top level; e.g. the following works as expected: {{{ {-# LANGUAGE PatternSynonyms #-} pattern Id x = x foo = x where Id x = True }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9889#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#9889: Pattern synonym does not work in top-level pattern bind -------------------------------------+------------------------------------- Reporter: goldfire | Owner: cactus Type: bug | Status: patch Priority: normal | Milestone: Component: Compiler (Type | Version: 7.9 checker) | Keywords: Resolution: | PatternSynonyms Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones ): In [changeset:"5830fc449af6b2c0ef5be409fd3457114ae938ca/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="5830fc449af6b2c0ef5be409fd3457114ae938ca" Pattern synonym names need to be in scope before renaming bindings (#9889) I did a bit of refactoring at the same time, needless to say }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9889#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#9889: Pattern synonym does not work in top-level pattern bind -------------------------------------+------------------------------------- Reporter: goldfire | Owner: cactus Type: bug | Status: closed Priority: normal | Milestone: 7.10.1 Component: Compiler (Type | Version: 7.9 checker) | Keywords: Resolution: fixed | PatternSynonyms Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Changes (by thoughtpolice): * status: merge => closed * resolution: => fixed Comment: Merged to `ghc-7.10`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9889#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler