Tony Firshman wrote:
gdgqler wrote, On 14/11/09 08:15:
On 8 Nov 2009, at 09:44, John Gilpin wrote:
Is there a way of stepping through a BASIC program, line by line, for
debugging purposes? If so how?
The way I debug BASIC programs is to use a routine called Puse, which
causes a pause.
DEFine PROCedure Puse
LOcal a$(2)
OPEN#20,con
a$=INKEY$(#20,-1)
CLOSE#20
END DEFine
By placing this inside the program I can see what's happening. For
example
2000 Fling: REMark some procedure
2005 Puse:PRINT "Line 2000":Puse
allows me to see if I have gone past line 2000. Pressing any key
allows the program to continue (to the next Puse).
You can add a PRINT facility to Puse by:
DEFine PROCedure(b$)
.
.
PRINT#20,b$
.
.
END DEFine
This works well even inside compiled BASIC programs.
... and of course further de-bugging info could be added, like printing
critical global variables each time.
Right you are. I miss Minerva SuperBasic's "watch variable" facility, eg:
120 WHEN x > 10: PRINT "X is now too big!"
..
130 FOR x = 5 TO 12: PRINT x
will print
5
6
7
8
9
10
X is now too big!
11
X is now too big!
12
Pity it didnt make it into SBasic
Per
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