[GHC] #393: functions without implementations

[GHC]

#393: functions without implementations
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              Reporter:  c_maeder    |            Owner:  simonpj
                  Type:  feature     |           Status:  new
  request                            |        Milestone:  ⊥
              Priority:  normal      |          Version:  None
             Component:  Compiler    |         Keywords:
  (Type checker)                     |     Architecture:  Unknown/Multiple
            Resolution:  None        |       Difficulty:  Moderate (less
      Operating System:              |  than a day)
  Unknown/Multiple                   |       Blocked By:
       Type of failure:              |  Related Tickets:
  None/Unknown                       |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by rodlogic):

 Adding the source file and line number is also quite useful. So shouldn't
 the definition proposed by @simonpj include them? Or is there a specific
 reason not to?

 In fact, shouldn't the exception thrown by {{{undefined}}} include the
 file & lineno so that the added definition would then become simply {{{f =
 undefined}}}, as requested in the original ticket? I have already been at
 a loss by an error such as {{{*** Exception: Prelude.undefined}}} without
 any references to where.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/393#comment:20>
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