[GHC] #10569: Optionally treat an out-of-scope variable like a typed hole (was: Treat an out-of-scope variable like a typed hole)

[GHC]

#10569: Optionally treat an out-of-scope variable like a typed hole
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        Reporter:  simonpj           |                Owner:
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.0.1
       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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Changes (by ertes):

 * status:  closed => new
 * version:  7.10.1 => 8.0.1
 * resolution:  fixed =>


Comment:

 Can we please make this behaviour optional, and ideally off by default? In
 an interactive rapid-prototyping workflow this is a major stumbling block,
 because you have to watch your code crash a few times until you have
 everything in place, particularly when you ''use now, import later''.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10569#comment:5>
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