Proposal: Deprecate ExistentialQuantification

Simon Peyton-Jones simonpj at
Fri Jul 24 03:00:50 EDT 2009

| On Friday 10 July 2009 5:03:00 am Wolfgang Jeltsch wrote:
| > Isn’t ExistentialQuantification more powerful than using GADTs for
| > emulating existential quantification? To my knowledge, it is possible to
| > use lazy patterns with existential types but not with GADTs.
| 6.10.4 doesn't allow you to use ~ matches against either.

In that respect GADTs and existentials are the same, regardless of the synatx with which they are declared.  I hope.


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