let a, b be Int-Location ; for s being State of SCM+FSA holds
( (Exec ((a := b),s)) . (IC ) = succ (IC s) & (Exec ((a := b),s)) . a = s . b & ( for c being Int-Location st c <> a holds
(Exec ((a := b),s)) . c = s . c ) & ( for f being FinSeq-Location holds (Exec ((a := b),s)) . f = s . f ) )
let s be State of SCM+FSA; ( (Exec ((a := b),s)) . (IC ) = succ (IC s) & (Exec ((a := b),s)) . a = s . b & ( for c being Int-Location st c <> a holds
(Exec ((a := b),s)) . c = s . c ) & ( for f being FinSeq-Location holds (Exec ((a := b),s)) . f = s . f ) )
consider A, B being Data-Location such that
A1:
a = A
and
A2:
b = B
and
A3:
a := b = A := B
by Def11;
reconsider S = s | SCM-Memory as State of SCM by Th73;
A4:
Exec ((a := b),s) = s +* (Exec ((A := B),S))
by A3, Th75;
hence (Exec ((a := b),s)) . (IC ) =
(Exec ((A := B),S)) . (IC )
by Th78
.=
succ (IC S)
by AMI_3:2
.=
succ (IC s)
by Th88
;
( (Exec ((a := b),s)) . a = s . b & ( for c being Int-Location st c <> a holds
(Exec ((a := b),s)) . c = s . c ) & ( for f being FinSeq-Location holds (Exec ((a := b),s)) . f = s . f ) )
thus (Exec ((a := b),s)) . a =
(Exec ((A := B),S)) . A
by A1, A4, Th79
.=
S . B
by AMI_3:2
.=
s . b
by A2, Th80
; ( ( for c being Int-Location st c <> a holds
(Exec ((a := b),s)) . c = s . c ) & ( for f being FinSeq-Location holds (Exec ((a := b),s)) . f = s . f ) )
let f be FinSeq-Location ; (Exec ((a := b),s)) . f = s . f
A8:
not f in dom (Exec ((A := B),S))
by Th68;
thus (Exec ((a := b),s)) . f =
(s +* (Exec ((A := B),S))) . f
by A4
.=
s . f
by A8, FUNCT_4:11
; verum