[GHC] #12540: RFC: Allow not quantifying every top-level quantifiee

[GHC]

#12540: RFC: Allow not quantifying every top-level quantifiee
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        Reporter:  Iceland_jack      |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      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):

 I've often wondered about this too.

 We could simply change the behaviour to always over quantify over un-
 mentioned tyvars.  That gives

 * Same behaviour when no `forall`
 * Same behaviour when you specify all variables
 * But accepts some extra programs.

 Adding a flag to control it seems overkill.

 Simon

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12540#comment:3>
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