let a be Data-Location; for il, k being Nat holds NIC ((a >0_goto k),il) = {k,(il + 1)}
let il, k be Nat; NIC ((a >0_goto k),il) = {k,(il + 1)}
set t = the State of SCM;
set Q = the Instruction-Sequence of SCM;
let x be object ; TARSKI:def 3 ( not x in {k,(il + 1)} or x in NIC ((a >0_goto k),il) )
set I = a >0_goto k;
A2:
IC <> a
by AMI_5:2;
assume A3:
x in {k,(il + 1)}
; x in NIC ((a >0_goto k),il)
reconsider n = il as Element of NAT by ORDINAL1:def 12;
reconsider il1 = n as Element of Values (IC ) by MEMSTR_0:def 6;
reconsider u = the State of SCM +* ((IC ),il1) as Element of product (the_Values_of SCM) by CARD_3:107;
reconsider P = the Instruction-Sequence of SCM +* (il,(a >0_goto k)) as Instruction-Sequence of SCM ;
per cases
( x = k or x = il + 1 )
by A3, TARSKI:def 2;
suppose A4:
x = k
;
x in NIC ((a >0_goto k),il)reconsider v =
u +* (a .--> 1) as
Element of
product (the_Values_of SCM) by CARD_3:107;
A5:
IC in dom the
State of
SCM
by MEMSTR_0:2;
not
IC in dom (a .--> 1)
by A2, TARSKI:def 1;
then A7:
IC v =
IC u
by FUNCT_4:11
.=
n
by A5, FUNCT_7:31
;
reconsider il =
il as
Element of
NAT by ORDINAL1:def 12;
A8:
P /. il = P . il
by PBOOLE:143;
il in NAT
;
then
il in dom the
Instruction-Sequence of
SCM
by PARTFUN1:def 2;
then A9:
P . il = a >0_goto k
by FUNCT_7:31;
a in dom (a .--> 1)
by TARSKI:def 1;
then v . a =
(a .--> 1) . a
by FUNCT_4:13
.=
1
by FUNCOP_1:72
;
then
IC (Following (P,v)) = k
by A7, A9, A8, AMI_3:9;
hence
x in NIC (
(a >0_goto k),
il)
by A4, A7, A9, A8;
verum end; suppose A10:
x = il + 1
;
x in NIC ((a >0_goto k),il)reconsider v =
u +* (a .--> 0) as
Element of
product (the_Values_of SCM) by CARD_3:107;
A11:
IC in dom the
State of
SCM
by MEMSTR_0:2;
not
IC in dom (a .--> 0)
by A2, TARSKI:def 1;
then A13:
IC v =
IC u
by FUNCT_4:11
.=
n
by A11, FUNCT_7:31
;
reconsider il =
il as
Element of
NAT by ORDINAL1:def 12;
A14:
P /. il = P . il
by PBOOLE:143;
il in NAT
;
then
il in dom the
Instruction-Sequence of
SCM
by PARTFUN1:def 2;
then A15:
P . il = a >0_goto k
by FUNCT_7:31;
a in dom (a .--> 0)
by TARSKI:def 1;
then v . a =
(a .--> 0) . a
by FUNCT_4:13
.=
0
by FUNCOP_1:72
;
then
IC (Following (P,v)) = il + 1
by A13, A15, A14, AMI_3:9;
hence
x in NIC (
(a >0_goto k),
il)
by A10, A13, A15, A14;
verum end; end;