defpred S1[ object , object , object ] means ex u, w being Function of X,L ex a being Element of L st
( w = $3 & a = $1 & u = $2 & w = a '*' u );
A0:
for x, y being object st x in the carrier of L & y in Funcs (X, the carrier of L) holds
ex z being object st
( z in Funcs (X, the carrier of L) & S1[x,y,z] )
proof
let x,
y be
object ;
( x in the carrier of L & y in Funcs (X, the carrier of L) implies ex z being object st
( z in Funcs (X, the carrier of L) & S1[x,y,z] ) )
assume B:
(
x in the
carrier of
L &
y in Funcs (
X, the
carrier of
L) )
;
ex z being object st
( z in Funcs (X, the carrier of L) & S1[x,y,z] )
then reconsider a =
x as
Element of the
carrier of
L ;
reconsider h =
y as
Element of
Funcs (
X, the
carrier of
L)
by B;
take z =
a '*' h;
( z in Funcs (X, the carrier of L) & S1[x,y,z] )
thus
z in Funcs (
X, the
carrier of
L)
by FUNCT_2:8;
S1[x,y,z]
thus
S1[
x,
y,
z]
;
verum
end;
consider h being Function of [: the carrier of L,(Funcs (X, the carrier of L)):],(Funcs (X, the carrier of L)) such that
A1:
for x, y being object st x in the carrier of L & y in Funcs (X, the carrier of L) holds
S1[x,y,h . (x,y)]
from BINOP_1:sch 1(A0);
take
h
; for f being Function of X,L
for a being Element of L holds h . (a,f) = a '*' f
hence
for f being Function of X,L
for a being Element of L holds h . (a,f) = a '*' f
; verum