[GHC] #9049: Expose srcLoc from the assertion architecture to allow better error messages

[GHC]

#9049: Expose srcLoc from the assertion architecture to allow better error
messages
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        Reporter:  nh2               |            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 simonmar):

 I actually like the wiki:ExplicitCallStack/ImplicitLocations idea, I'm
 just worried that if we have it then we'll have people who want location-
 abstracted versions of all the partial functions in base, and that's a lot
 of extra clutter.  If we could provide the feature but draw the line at
 using it in APIs (except for `error`, `undefined`, `throw`, and other
 things that explicitly raise exceptions) then I'm all for it.

 I realise that then you don't get automatic `head []` locations.  But it
 doesn't stop someone from defining their own location-abstracted `head`,
 or indeed making a package of location-abstracted partial functions from
 base.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9049#comment:8>
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