TypeFamilies vs. FunctionalDependencies & type-level recursion

AntC anthony_clayden at clear.net.nz
Fri Jun 8 03:00:26 CEST 2012

Simon Peyton-Jones <simonpj at ...> writes:

> I have expanded the draft spec on
> http://hackage.haskell.org/trac/ghc/wiki/NewAxioms

Thanks Simon, that's much clearer.

By the way, are the examples for the multi- type instance declarations quite 
as intended? The heads have no head, as it were. Did you mean, or is this 

    type instance F [a] where ...

    type instance F (a, b) where ...

(From a documentation point of view, this shows that the instance groups are 

> to answer some of the questions on AntC’s discussion page.

(I'd rather you called it just *the* discussion page; I'm doing the ego-less 
contributor thing. I must admit that after I got the page started, I've not 
had so much time to keep building it.)


More information about the Haskell-prime mailing list