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[Julien Tesson <julien.tesson AT univ-orleans.fr>]

Le 11/10/2012 10:47, Arnaud Spiwack a écrit :
> Yes.
>
> It's occasionally useful to be able to compute with existential variables.
>
> Why is it strange ?
It looked strange for me at first because I would have expected the same 
behaviour (in term of failure) between  [Eval compute in a] and [Definition x 
:= Eval compute in a], and because when I use type classes, I expect that the 
instance search mechanism warn me when it failed to find a matching instance.

This new behaviour seems interesting  but I found it surprising at first.

Regards,
Julien