ExistentialQuantifier

[Ben Rudiak-Gould]

Ross Paterson wrote:
> I don't think the original name is inappropriate: the feature described
> is certainly existential quantification, albeit restricted to
> alternatives of data definitions.

I think that "existential quantification" should mean, well, existential 
quantification, in the sense that term is used in logic. I don't like the 
idea of using it for the feature currently implemented with "forall" in 
front of the data constructor, given that these type variables are 
universally quantified in the data constructor's type. How about changing 
the name to "existential product types" or "existential tuples"? I would 
even suggest "boxed types", but that's already taken.

-- Ben