scheme :: PCOMPS_1:sch 1
Lambda1top{ F₁() -> TopSpace, F₂() -> Subset-Family of F₁(), F₃() -> Subset-Family of F₁(), F₄( object ) -> Subset of F₁() } :

ex f being Function of F₂(),F₃() st
for Z being Subset of F₁() st Z in F₂() holds
f . Z = F₄(Z)

provided

A1: for Z being Subset of F₁() st Z in F₂() holds
F₄(Z) in F₃()