[GHC] #12188: Pattern variables bound by PatternGuards are not accessible in where clause

GHC ghc-devs at haskell.org
Tue Jun 14 15:33:18 UTC 2016


#12188: Pattern variables bound by PatternGuards are not accessible in where clause
-------------------------------------+-------------------------------------
        Reporter:  heisenbug         |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:  invalid           |             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:                    |
-------------------------------------+-------------------------------------

Comment (by rwbarton):

 Since a single where block can scope over multiple guarded right-hand
 sides, it doesn't make sense to have variables bound in a guard be in
 scope in the body of the where clause anyways.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12188#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler


More information about the ghc-tickets mailing list