Re: Thanks, and new question re existensials

[Christopher Jeris]

On Thu, 4 Nov 1999, Peter Ross wrote:
> Existential types tend to be most useful when combined with
> typeclasses.  This is because you don't know what type is being
> returned, however you do know an interface which can be used with this
> type.

So this is a way to dodge the concrete-type-dependent destructuring that
so often arises in ML, Haskell, other "sum-type-centric" languages?
How does this solution compare to something like views, as in Okasaki's
proposal for SML (http://www.cs.columbia.edu/~cdo/ml98views.dvi) ?  
I can see all this neat stuff but I don't have the background to make
intelligent comparisons...

thanks & peace,
Chris Jeris