[Template-haskell] RE: [ ghc-Bugs-820778 ] Malformed Predicate w/ Template Haskell

[Wolfgang Thaller]

> TH maestros
>
> This bug turns out to be simply that Template Haskell is only set up 
> for
> Haskell 98, whereas Jon Cast wants to manipulate multi-parameter type
> clases.
>
> Should we add multi-param type classes to THSyntax?  Does anyone feel
> like doing it?  It's a fairly routine matter, but it does mean changing
> the data type.  (Another reason to use bracket syntax!)
>
> Simon

Hmmm... I've been using some simple multi-param type classes (no 
fundeps) with Template Haskell and GHC from the STABLE cvs tree, and 
I've experienced no problems, so I thought they were supported.
They *are* a very useful feature that I don't think I could do without 
- what needs to be done to keep them at least as supported as they are 
now?

Cheers,

Wolfgang