Metamath Proof Explorer


Syntax definition wl-reu

Description: Redefine the restricted existential uniqueness context to avoid overloading and syntax check errors in mmj2. This operator is to be distinguished from E! x e. A ph with a similiar semantics, but using x as a formal parameter rather than assuming true elementhood.

Ref Expression
Assertion wl-reu wff ∃! x : A φ