Deriving Typeable instances

[Simon Peyton-Jones]

Yes, you could I suppose.  But then there'd be a different peculiar
change in behaviour at arity 7.  I'm not sure that'd be an advantage.

Simon

| -----Original Message-----
| From: Simon Marlow
| Sent: 10 August 2005 10:58
| To: Simon Peyton-Jones; Frank Huch; glasgow-haskell-bugs at haskell.org
| Subject: RE: Deriving Typeable instances
| 
| On 09 August 2005 17:16, Simon Peyton-Jones wrote:
| 
| > I'm not against this, although you can work around the problem by
| > adding a library that defines the missing type classes (Typeable8,
| > Typeable9 etc), and making your compiler generate the instance
| > itself.  There is nothing magic about 'deriving'; it's just
| > convenient.
| 
| If the arity is >7, couldn't we just generate a Typeable instance,
rather than the TypeableN instance?
| It would mean you wouldn't get the benefits of TypeableN, but at least
you'd have Typeable.
| 
| Cheers,
| 	Simon