[Haskell-cafe] More experiments with ATs

[Andrew Coppin]

Brent Yorgey wrote:
> On Sun, Jul 04, 2010 at 10:31:34AM +0100, Andrew Coppin wrote:  
>   
>> I have literally no idea what a type family is. I understand ATs (I think!), 
>> but TFs make no sense to me.
>>     
>
> ATs are just TFs which happen to be associated with a particular
> class.  So if you understand ATs then you understand TFs too, you just
> didn't know it. =)
>   

How would that make sense though? I'm having trouble forming a mental 
image of how / why you'd use that...