Existential types: want better syntactic support (autoboxing?)

[Wolfgang Jeltsch]

Am Montag, 30. Januar 2006 19:02 schrieb Duncan Coutts:
> [...]

> I have often thought that it would be useful to have an existential
> corresponding to a class.

How would this work with multi-parameter classes, constructor classes, etc.? 
If you propose something that only works in conjunction with a special kind 
of classes I would hesitate to include such thing in a Haskell standard.

I think that it would often be nice to have Template Haskell standardized and 
implement features like autoboxing via some library using Template Haskell.  
This way, we would keep the actual language small but open the door for lots 
of useful extensions.  This principle of a small but powerful (extensible) 
language is used already a lot without Template Haskell, so why not use it 
also in conjunction with Template Haskell in cases like the autoboxing 
approach.

> [...]

Best wishes,
Wolfgang