set f = 0 .--> NAT;
A1:
dom (0 .--> NAT) = {0}
by FUNCOP_1:13;
B2:
rng (0 .--> NAT) c= {NAT}
by FUNCOP_1:13;
{NAT} c= N \/ {NAT}
by XBOOLE_1:7;
then
rng (0 .--> NAT) c= N \/ {NAT}
by B2, XBOOLE_1:1;
then reconsider f = 0 .--> NAT as Function of {0},(N \/ {NAT}) by A1, RELSET_1:4;
reconsider y = 0 as Element of {0} by TARSKI:def 1;
take
Mem-Struct(# {0},y,f #)
; ( the carrier of Mem-Struct(# {0},y,f #) = {0} & the ZeroF of Mem-Struct(# {0},y,f #) = 0 & the Object-Kind of Mem-Struct(# {0},y,f #) = 0 .--> NAT )
thus
( the carrier of Mem-Struct(# {0},y,f #) = {0} & the ZeroF of Mem-Struct(# {0},y,f #) = 0 & the Object-Kind of Mem-Struct(# {0},y,f #) = 0 .--> NAT )
; verum