See all articles from SLUG Newsletter Aug 1987
Key in this short listing to trace the variables in your program. Place it in front of your program and GO TO 5 to use it. You will get a list of the lines that the variable you are looking for is in.
BASIC Listing
5 INPUT "Variable to view ",v$: LET l=LEN v$
10 LET p=PEEK 23635+256*PEEK 23636
15 LET v=PEEK 23627+256*PEEK 23628
20 LET n=256*PEEK p+PEEK (p+1)
25 LET le=PEEK (p+2)+256*PEEK (p+3)
30 PRINT n
35 LET q=0: LET c=1: FOR j=4 TO le+4
40 LET p1=PEEK (p+j)
45 IF p1=34 THEN LET q=NOT q
50 IF q THEN GO TO 90
55 IF p1=14 THEN LET j=j+5: GO TO 90
60 IF p1=58 THEN LET c=c+1
65 IF p1<>CODE v$(1) THEN GO TO 90
70 FOR k=1 TO l
75 LET p1=PEEK (p+j+k-1): IF p1<>CODE v$(k) THEN GO TO 90
80 NEXT k: LET k=PEEK (p+j+k-1): IF k=36 OR (k>47 AND k<58) OR (k>64 AND k<90) OR (k>96 AND k<123) THEN GO TO 90
85 PRINT FLASH 1; INK 2; PAPER 7;n;: PRINT INK 9;TAB 5;":";c;TAB 10;v$
90 NEXT j
95 LET p=4+p+le: IF p=v THEN STOP
100 GO TO 20.
9998 SAVE "TRACE" LINE 0
Note: Type-in program listings on this website use ZMAKEBAS notation for graphics characters.