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Re: prototype board options
sfahey wrote:
To: Michael J. Mahon
On 2/13/08 1:00 PM, in article 9oKdnfN9Gu3goy7anZ2dnUVZ_umlnZ2d@comcast.com,
"Michael J. Mahon" <mjmahon@aol.com> wrote:
I've never encountered this phrase in reference to breakpoint debugging,
so it must be a "local idiom".
I've heard this phrase and similar ones since the '70s, mostly from comp-sci
and mainframe programmer operators trained in the technique, as well as most
accomplished knitters.
Curious--been there, done that... Must have run in different circles.
;-)
Actually, was never much for breakpoint debugging, myself--though it has
its uses.
I've always been a "behavioral" debugger, meaning that I observe a
programs deviations from expected behavior and then locate the bug
by deduction. In cases of (my) confusion, I insert print statements
instead of breakpoints.
Often, I incorporate useful intermediate result print statements
that are conditional on the value of a debug variable. These are
frequently valuable long after the program is working. If resources
are tight, they can always be conditionally compiled.
This was combined (in the mainframe days) with dump debugging
after a crash. Then you had all the behavior to examine (debugging
print statements) plus the opportunity to examine all the data
structures at the end, and could find any as yet unmanifested
errors in them.
Although we often got only one or two turnarounds a day, with careful
study of the dumps it was possible to kill several bugs per turnaround.
A day or two of that and things were usually working pretty well. ;-)
One great advantage of programming a relatively slow, interactive
machine like the Apple II, is that you can often observe the order
of the undesired behaviors as well, simplifying the search for the
reason(s).
-michael
NadaPong: Network game demo for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
tool--and it's seriously underused."