[GHC] #15050: ScopedTypeVariables could allow more programs

[GHC]

#15050: ScopedTypeVariables could allow more programs
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Your patch looks fine.  Easiest to leave `SigTv` alone; and just change
 what sort of tyvar is used in a pattern type signature; which is what you
 have done.

 It's a simple change.  Just a question of deciding what we want.  I'm ok
 with binding a type variable to an arbitrary type.   GHC proposal?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15050#comment:14>
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