[GHC] #14998: Sort out the strictness mess for exceptions

[GHC]

#14998: Sort out the strictness mess for exceptions
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.3
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  Exceptions
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 sgraf):

 Also shouldn't `catch#` at least be head-strict in its first argument? I'm
 pretty sure that would get rid of the bang pattern I had to introduce,
 while still having correct semantics: An `IO` action which throws ''when
 executed'' triggers the exception handler, while a call like `catch
 undefined h == undefined`, something I would expect.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14998#comment:18>
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