ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  ciun Unicode version

Syntax Definition ciun 3781
Description: Extend class notation to include indexed union. Note: Historically (prior to 21-Oct-2005), used the notation  U. x  e.  A B, with the same union symbol as cuni 3704. While that syntax was unambiguous, it did not allow for LALR parsing of the syntax constructions in The new syntax uses as distinguished symbol  U_ instead of  U. and does allow LALR parsing. Thanks to Peter Backes for suggesting this change.
Ref Expression
vx  setvar  x
cA  class  A
cB  class  B
Ref Expression
ciun  class  U_ x  e.  A  B

See definition df-iun 3783 for more information.

Colors of variables: wff set class
  Copyright terms: Public domain W3C validator