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Bounded Existential Quantification and Partial Abstraction
Bounding existential quantifiers:
exists
a <=t. t'
exists
a. t :=
exists
a <=Top. t
Partially abstract
types:
a
is abstract.
We know
a
is subtype of
t
.
a
is not more abstract than
t
is.
Modified packing construct:
pack [a <= t = t' in t"] e
Author:
Wolfgang Schreiner
Last Modification: May 27, 1998