[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


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