[Haskell-cafe] Typeclass resolution errors quite puzzling

Francesco Ariis fa-ml at ariis.it
Mon Aug 15 13:38:45 UTC 2016

On Mon, Aug 15, 2016 at 02:35:15PM +0100, Tom Ellis wrote:
> My complaint is about the confusing error message, not the failure to
> type check.

For reference, feeding that program to Hugs (which I usually
find a bit better in terms of error reporting) leads to:

    ERROR "prova.hs":5 - Instance of Eq B required for definition of main

Slightly clearer but not much. I don't have UHC handy to test
its error messages!

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