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"\n" is displayed weirdly in error messages

Observe:

Prelude> "a\nb" + ()

<interactive>:2:10:
    Couldn't match expected type ‘[Char]’ with actual type ‘()’
    In the second argument of ‘(+)’, namely ‘()’
    In the expression:
      "a\n\
      \b"
      + ()

Moreover, if “\n” is at the end of the string, it simply gets eaten:

Prelude> "a\n" + ()

<interactive>:3:9:
    Couldn't match expected type ‘[Char]’ with actual type ‘()’
    In the second argument of ‘(+)’, namely ‘()’
    In the expression: "a" + ()

It happens in GHC as well as GHCi. Tested on 7.8.3.

Trac metadata
Trac field Value
Version 7.8.3
Type Bug
TypeOfFailure OtherFailure
Priority low
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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