Lazy type-class resolution

Tomasz Zielonka t.zielonka at
Fri Aug 13 06:50:01 EDT 2004

On Fri, Aug 13, 2004 at 09:03:53AM +0100, Simon Peyton-Jones wrote:
> Yes, when *inferring* types GHC defers context reduction as long as
> possible.  Reason: the call site of the function may "see" more instance
> declarations (e.g. in particular, overlapping ones), so doing reduction
> later may yield a different answer.  

Thanks for explanation.

Besides overlapping instances, what are the other mechanisms that could
change the decision later? I can't think of any, are they only

Best regards,

.signature: Too many levels of symbolic links

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