[GHC] #9478: Partial type signatures

[GHC]

#9478: Partial type signatures
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        Reporter:  simonpj           |                Owner:
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.8.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  partial-
                                     |  sigs/should_compile/PatBind2
                                     |  partial-
                                     |  sigs/should_compile/EqualityConstraint
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D168
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"e1ff2b4950a02bc26b9ab36c9c589a8156e324bd/ghc"
 e1ff2b49/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="e1ff2b4950a02bc26b9ab36c9c589a8156e324bd"
 Fix partial sigs and pattern bindings interaction

 It turns out that GHC 8.0 would accept entirely bogus
 programs like

    f2 :: (True, _) -> Char
    Just f2 = Just (\x->x)

 (which is now partial-sigs/should_fail/PatBind3)

 This also fixes Trac #9478, test `PatBind2`.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9478#comment:7>
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