Syntax Definition ciin 3971

Description: Extend class notation to include indexed intersection. Note: Historically (prior to 21-Oct-2005), set.mm used the notation ∩x ∈ AB, with the same intersection symbol as cint 3927. Although that syntax was unambiguous, it did not allow for LALR parsing of the syntax constructions in set.mm. The new syntax uses a distinguished symbol ∩ instead of ∩ and does allow LALR parsing. Thanks to Peter Backes for suggesting this change.

Hypotheses

Ref	Expression
vx	setvar x
cA	class A
cB	class B

Assertion

Ref	Expression
ciin	class ∩x ∈ A B

See definition df-iin 3973 for more information.