Proposal: Deprecate ExistentialQuantification

[Malcolm Wallace]

> I would hereby like to propose that the
> ExistentialQuantification extension is deprecated.

It is worth pointing out that all current Haskell implementations (to  
my knowledge) have ExistentialQuantification, whilst there is only one  
Haskell implementation that has the proposed replacement feature, GADTs.

Of course, that in itself is not an argument to avoid desirable change  
to the language, but it is one factor to consider.

Regards,
     Malcolm