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Confusing warning message for incomplete patterns

The following code

{-# OPTIONS_GHC -Wall #-}

import Data.Word

f :: Word8 -> Bool
f 0 = True
f 1 = False
f 2 = True

Produces the warning

7:1:
    Warning: Pattern match(es) are non-exhaustive
             In an equation for `f':
                 Patterns not matched: #x with #x `notElem` [0#, 1#, 2#]

While accurate, this is not exactly user friendly.

Found in GHC 7.4.1 RC 1

Trac metadata
Trac field Value
Version 7.3
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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