[GHC] #13917: The line on which to locate the error indication is bad.

[GHC]

#13917: The line on which to locate the error indication is bad.
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        Reporter:  vanto             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by goldfire):

 The correction to the code is irrelevant for parsing errors: GHC just
 reports where it first encounters a parsing error. There is no promise
 that a fix is available on that line -- indeed, in this case it's just a
 stroke of luck that there is.

 While it's conceivable to imagine some program analysis tool that uses
 heuristics to do what you want -- make the suggestion an expert Haskeller
 would make -- that is well beyond the scope of what GHC does. The amount
 of engineering would be huge. Perhaps this kind of tool would pay off in
 the long run (imagine always having an "expert Haskeller" at your side
 while programming!), it doesn't seem necessary to tie such a tool into
 GHC.

 So, my recommendation is to treat the current behavior as correct and move
 onto other problems.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13917#comment:7>
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