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Location in -fdefer-type-errors

Consider

x :: Char
x = 'x' + 1

y :: Char
y = 'y' + 1

Run ghci -fdefer-type-errors:

*Main> x
*** Exception: G.hs:5:9:
    No instance for (Num Char) arising from a use of `+'
    In the expression: 'y' + 1
    In an equation for `y': y = 'y' + 1
(deferred type error)
*Main> y
*** Exception: G.hs:5:9:
    No instance for (Num Char) arising from a use of `+'
    In the expression: 'y' + 1
    In an equation for `y': y = 'y' + 1
(deferred type error)

The first exception is wrong. It seems that the missing Num Char instance is filled with the same error message in all places where the constraint should be supplied.

Trac metadata
Trac field Value
Version 7.6.2
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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