[Haskell-cafe] Instance match surprise

Tom Ellis tom-lists-haskell-cafe-2013 at jaguarpaw.co.uk
Tue Feb 2 06:38:25 UTC 2016

On Mon, Feb 01, 2016 at 11:56:58PM +0100, Wojtek Narczyński wrote:
> On 01.02.2016 21:29, Tom Ellis wrote:
> >If you want to know*why*  the instance contexts are ignored then you'll have
> >to ask someone who knows more about Prolog:)
> I think I know. There is really no way of knowing that there is no
> vicious little instance Eq ANY lurking deep down some obscure
> useless module. It is called: open world assumption.

Yes, Ben's explanation was a good one.

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