ghci obscurity

Frederik Eaton frederik at a5.repetae.net
Sat May 21 09:34:16 EDT 2005


Often ghci will give me the following message instead of something
helpful:

Top level:
    No instance for (Show (IO ()))
      arising from use of `print' at Top level
    Probable fix: add an instance declaration for (Show (IO ()))
    In a 'do' expression: print it

I don't know how hard it would be to fix, but it's kind of a nuisance.
It seems to only come up when something else is wrong, but it often
comes up *instead* of a good error message for the real problem,
making it very hard to track the real problem down.

Frederik

-- 
http://ofb.net/~frederik/



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