[GHC] #15559: fromJust has no HasCallStack

[GHC]

#15559: fromJust has no HasCallStack
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Core Libraries    |              Version:  8.4.3
      Resolution:                    |             Keywords:  newcomer
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 chessai):

 > I really like GHC's internal HasDebugCallStack, which disappears (that
 is, becomes ()) when DEBUG is not defined via CPP and becomes HasCallStack
 when DEBUG is defined. As far as I know, there's no standard way to mark a
 build meant for debugging, but perhaps there should be. Then, we could do
 the same for all applications instead of just GHC.

 In addition to making this available to users of GHC, there should
 probably be an additional side-effect to the DEBUG flag, or a separate
 flag, that turns HasDebugCallStack on for all functions

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15559#comment:6>
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