Syntax Definition wralseu 17135

Description: Extend wff definition to include "all some one" applied to a class, which means ps is true whenever ph is true for x in A, and exactly one x in A satisfies ph. (Contributed by David A. Wheeler, 22-Jul-2026.)

Hypotheses

Ref	Expression
wph	wff ph
wps	wff ps
vx	setvar x
cA	class A

Assertion

Ref	Expression
wralseu	wff A.E! x e. A ( ph -> ps )

See definition df-ralseu 17137 for more information.