[GHC] #9030: An async exception handler that blocks throwTo until handler finishes running

[GHC]

#9030: An async exception handler that blocks throwTo until handler finishes
running
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        Reporter:  jberryman         |            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      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by jberryman):

 Sure, but the `throwTo` is something the users of my library are doing. Or
 maybe they're using the `async` lib which is doing the `throwTo
 ThreadKilled`.

 In this particular case I think the user will have a mental model of what
 should happen when a blocked reader thread is killed (which matches the
 behavior of standard `Chan`), and I'd rather just be able to implement
 that rather than document weird corner-cases or force users to use a
 particular function or `Exception` type (although thanks for that idea;
 I'll probably warm up to that as a workaround).

 Maybe users never in practice think or care much about what happens when
 they do a `throwTo` and I just have to worry about not leaving my data
 structure broken; I'm not really sure.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9030#comment:2>
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