Tandy 1000 Basic Reference Manual page 111

Chapter 10 I
BASIC
Keywords
Sample Program
1
1 0 REM T H I S PROGRAM DEMONSTRATES C H A I N I N G U S I N G
2 0 REM S A V E T H I S MODULE ON D I S K A S "PROGI
.BAS"
30 D I M A S C 2 ) , B S ( 2 )
4 0 COMMON A S 0 , B S O
5 0 A S < l ) = " V A R I A B L E S I N COMMON MUST B E A S S I G N E D
"
6 0 A $ ( 2 ) = " V A L U E S B E F O R E C H A I N I N G "
7 0
BS
(
1
1
= " I '
:
BS ( 2 )
= " I '
8 0 C H A I N
" p r o g 2 . b a 5 "
9 0 P R I N T
:
P R I N T B S C I ) : P R I N T
:
P R I N T B S ( 2 ) :
1 0 0 E N D
Save this program as progl.bas, using the A option (Enter:
SAVE
"progl.bas", A). Enter
NEW,
and then enter the following
program.
COMMON TO P A S S V A R I A B L E S .
U S I N G T H E A O P T I O N .
P R I N T
1 0 REM T H E S T A T E M E N T " D I M A S ( 2 ) , B S ( 2 ) " MAY ONLY
20 REM H E N C E , I T DOES NOT APPEAR I N T H I S M O D U L E .
3 0 REM S A V E T H I S MODULE ON T H E D I S K A S
4 0 COMMON A S 0 , B S O
5 0
P R ' I N T : P R I N T A S ( l ) ; A S ( 2 )
6 0 B $ ( I ) = " N O T E HOW T H E O P T I O N
OF S P E C I F Y I N G A
S T A R T I N G L I N E NUMBER"
7 0 B $ < 2 ) = " W H E N C H A I N I N G A V O I D S T H E D I M E N S I O N
S T A T E M E N T I N ' P R O G I
'
.
"
8 0 C H A I N
" p r o g l
. b a 5 " , 9 0
9 0 E N D
B E E X E C U T E D O N C E .
" P R O G 2 . B A S " U S I N G T H E A O P T I O N .
Save t h i s program a s prog2.bas, using the A option. Load
progl .bas and run it. Your screen should display:
V A R I A B L E S I N COMMON MUST B E A S S I G N E D V A L U E S
B E F O R E C H A I N I N G .
N O T E HOW T H E O P T I O N OF S P E C I F Y I N G
A S T A R T I N G
L I N E NUMBER
WHEN C H A I N I N G A V O I D S T H E D I M E N S I O N S T A T E M E N T I N
' P R O G I
'
.
109