[Haskell] Proposal: Allow "\=" for field update in record update
syntax
Keean Schupke
k.schupke at imperial.ac.uk
Fri Mar 4 10:32:15 EST 2005
robert dockins wrote:
>
> Is that really how this is done? That doesn't seem like it can be right:
>
> instance X (a b) -- single parameter class where 'a' has an arrow kind
>
> is very different from:
>
> instance X a b -- multiple parameter class
>
> I would expect a type constructed with 'appT' to correspond to the
> first declaration, and not to the second.
>
Yup, thats how it is done, I have some complex working TH that generates
multi parameter classes with fundeps
instances etc... and I can say for definite it all works fine:
For the above examples
appT X (appT a b) -- X is applied once (to a applied to b)
appT (appT X a) b -- X is applied twice first to a then to b
Keean.
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