[jhc] building transformers library, irrefutable patterns

John Meacham john at repetae.net
Tue Aug 10 04:29:53 EDT 2010

On Tue, Aug 10, 2010 at 08:23:17AM +0000, Korcan Hussein wrote:
> Cool, on a related note does jhc support type families? I think I read
> a previous update that mentions using type families for some module
> but that might have been the implementation of jhc rather than support
> in jhc?

No, not yet. Though, type families are particularly easy to implement in
jhc due to the way it does classes and data families are
practically free. So there is a fairly good chance jhc will have data
family support before even MPTCs (which are fairly tricky in jhc
actually). They will likely take the form of 'associated data types' on
first iteration rather than top level type families, it makes things
easier to attach them to type classes. 

I don't have a firm timeline on when I will get to implementing them,
but data families won't be too much work if there is a compelling need
for them.


John Meacham - ⑆repetae.net⑆john⑈ - http://notanumber.net/

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