GHC's error messages are too verbose?

Matthew Danish mdanish at
Sat Apr 14 11:45:19 EDT 2007

The verbosity is both a boon and a hinderance.  Personally, I don't
mind the extra information, but I'm fairly certain it causes alarm in
many newbies (judging from questions on #haskell).

For example, a simple type error like using (+) with a Char results

    No instance for (Num Char)
      arising from the literal `1' at file:pos
    Possible fix: add an instance declaration for (Num Char)
    In the first argument of `(+)', namely `1'
    In the expression: 1 + 'c'
    In the definition of `it': it = 1 + 'c'

That's a lot of terminology a typical newbie might not understand yet,
also, the suggested resolution is well off the mark.

I'm not saying that the error messages should be dumbed down
necessarily, but that the beginner's perspective may be worth

-- Matthew Danish -- user: mrd domain:
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