Typechecker / OverloadedStrings question 7.8 vs. 7.10

Daniel Bergey bergey at teallabs.org
Sun Aug 2 16:58:25 UTC 2015

On 2015-07-31 at 08:59, Simon Peyton Jones <simonpj at microsoft.com> wrote:
> Daniel Bergey wrote:
> |  How hard would it be to give a different error message instead of "No
> |  instance ..." when the type variable is ambiguous?  I always find this
> |  error slightly misleading, since it seems to me that there are
> |  multiple valid instances, not that there is "no instance".
> What would you like it to say?  I think it likely we could make it say that!

Great!  I'd like it to say "Multiple instances for ..."  or "No unique
instance for ...".  I have a slight preference for the former.


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