On 03/30/2012 05:58:49 PM, Platonides - Platonides(a)gmail.com wrote:
On 30/03/12 17:17, Jim Laurino wrote:
I also remember Dijkstra, who wrote, long ago
now, "no amount of testing
can prove the absence of defects", and made the unassailable case, at
least for me, that defects had to be prevented by design. This is
essentially the "discovery" that the author of the referenced note
describes. I can not recommend "Notes on structured programming" enough.
A pdf reprint of the book "Structured Programming", which contains it,
is available through the ACM. Note that all 3 authors later,
independently received Turing awards.
I think you mean these ones ? :)
http://www.cs.utexas.edu/users/EWD/ewd02xx/EWD249.PDF
(I just tried to send this, but the text below appears to have been truncated,
so I am trying again. My apologies if this is a duplicate)
Yes, that is the manuscript that was circulated, it makes the major points,
but there was also eventually a small book published, which is now available
again as part of the ACM Classic Book Series, see:
http://dl.acm.org/citation.cfm?id=1243380&jmp=cit&coll=portal&d…
The 3 authors are: O.-J. Dahl, E. W. Dijkstra, and C. A. R. Hoare
See the abstract by Hoare, on the ACM site, for a better appreciation of the
book.
also, from the notes at
http://en.wikipedia.org/wiki/Structured_programming
"This volume includes an expanded version of the Notes on Structured
Programming, above, including an extended example of using the structured
approach to develop a backtracking algorithm to solve the 8 Queens problem."
He expanded the original manuscript text in the book version at the suggestion
of Niklaus Wirth to give an example of what he meant. It is such a good
exposition of program development that I never bothered to actually run it,
because it was so obvious that it would work correctly.
--
Jim Laurino
wican.x.jimlaur(a)dfgh.net
Please direct any reply to the list.
Only mail from the listserver reaches this address.