Changes to Typeable

wren ng thornton wren at
Sun Feb 12 06:59:19 CET 2012

On 2/11/12 8:12 PM, John Meacham wrote:
> On Sat, Feb 11, 2012 at 5:05 PM, Roman Leshchinskiy<rl at>  wrote:
>> IMO, polymorphic kinds are far too experimental at this stage to be used in such a fundamental library. I also fully agree with Ian's point about other implementations.
>> Should there perhaps be a NewTypeable module which could then be renamed into Typeable once it is sufficiently well established?
> I hate using things like 'new', 'old', 'unsafe' in module names, the
> words are too overloaded and mean different things in different
> contexts. you end up with things like 'NewerTypeable'. So why not call
> it what it is already known by,  'Data.PolyTypeable'.

+1. Both for leaving it out of the way until kind polymorphism and the 
design have solidified a bit more (how far away is 7.6/7.8 exactly?), 
and for avoiding the use of "new"/"old" when other names are sensible.

Though I do support the change eventually. Having seven different 
Typeable classes just for different kinds is horrific, and it'll be nice 
to see all that washed away with a proper kind-polymorphic class.

Live well,

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