Re: DOW vs DOU

Brian Johnson wrote:
> 
>  ----------
> From:  Rick Baird
> Sent:  Thu, May 29, 1997 20:58 PM
> Subject:  Re: DOW vs DOU
> 
> Since were on the subject, I would like some opinions on a coding
> technique that I've been using for several years now.  I use the LEAVE
> and ITER opcodes extensively as a sortof GOTO replacement (ooh, maybe
> 
> ...(cut)...
> 
> Sort of GOTO?  ITER and LEAVE are *exactly* GOTO's, crutches for folks
> who don't *get* structured programming.  Stop using them!  Learn how to
> write structured programs!  Take a class!
> 
> Well, sorry, but that's my opinion.  Now that I've got that off my chest,
> here's an approach that avoids GOTO, ITER and LEAVE:
Oh boy, this is going to be fun. Here is my radical opinion on GOTO.

STRUCTURED PROGRAMING IS NOT "GOTO-LESS" PROGRAMMING.
By definition, A Structurded program has only one entry point, and one
exit point.
Taking this to a lower level, each module (paragraph, procedure,
subroutine), will have one entry and one exit point.

If a "GOTO" (or it's equivalent ie. LEAVE) branches to the exit of the
module, it is still structured! 

If a GOTO prevents you from having a structured program, so will an IF,
DO, CAS, etc.
Because all these are tests that cause what?, A goto to a location where
the code to be executed resides!

I wish I could find a communication program I wrotew on the S/38 to
communicate with an LU1 device on a mainframe. Writing "Structured" code
resulted in almost unreadable, and in-efficient code. Judicious use of
GOTOs lead to a clearly readable program, with greater efficiency.  All
GOTOs were to the exit of a paragraph (Sorry, this program was in COBOL,
but the same holds true for RPG)

That's my story, and I'm stickin' to it.
-- 
Bob Larkin
Larkin Computer Consulting
blarkin@wt.net
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