RE: ILE RPG:Is the use of ITER & LEAVE Structured Programming?

Folks,

All this discussion about structured vs non-structured seems to me a bit
misplaced in time. I remember 20 years ago in my university days there
was a lot of heated discussions on this topic in a computer press, but
since that time interest to this topic somewhat subsided.

At that time, after aggressive attacks on GOTO usage,  it was generally
agreed that GOTO or similar operation is sometimes needed to make a
complicated algorithm more readable and maintainable (there was
classical paper about it by Knuth, if I remember it right). Since GOTO
has become a taboo, ITERATE and LEAVE operations were introduced by some
of the computer science gurus of the time (I do not remember the name).

So, ITERATE and LEAVE operations ARE structured programming by
definition. So real purist will have to accept it. Of course, they have
every right to dislike them personally, but then they will no longer be
purists.


Regards, Alexei



        -----Original Message-----
        From:   Rick Baird [SMTP:rbbaird@Premsys.com]
        Sent:   Thursday, April 23, 1998 3:47 PM
        To:     MIDRANGE-L@midrange.com
        Subject:        Re: ILE RPG:Is the use of ITER & LEAVE
Structured Programming?

        Frank,

        I use leave and iter all the time, and I consider my programs
very structured and easy to read.   Yes, at first glance, it seems as
        if they are just goto's without tags, but, when used as directed
they subtract complexity and improve readability.

        If you have to introduce complexity or inhibit readability to
conform to an arbitrary set of rules, you are defeating the purpose of
        structured programming.

        These opcodes are simply another tool in your tool box, and like
any tool can be used effectively, as well as abused.  

        2cents(*off)

        regards,

        rick

        frank.meaney@nellcorpb.com wrote:
        >
        >Hi Folks,
        > 
        >I was just looking at a printout from the News400.com website
about
        >RPG ILE (tips and techniques). I belive the text was authored
by
        >Bryan Meyers. However he mentioned the use of ITER and LEAVE in
the
        >context of structured programming.
        >
        >I suppose I am a purist and I ensure that these opcodes are not
part
        >of any new development that we produce. IMHO these opcodes are
GOTO's
        >without TAGs and are not structured programming. I'd love to
hear
        >other opinions on this. And what is a strict defination of
Structured
        >programming.
        > 
        >Regards,
        > 
        >Frank Meaney.
        >      (Unisoft Systems Ltd)
        > 
        > 
        > 
        > 
        > ______________________________ Forward Header
__________________________________
        > Subject: Re: ILE RPG
        > Author:  <MIDRANGE-L@midrange.com > at NPB-INTERNET-MAIL
        > Date:    4/19/98 4:49 PM
        > 
        > 
        > >Hi Guys...What would be the easy to learn ILE RPG. I have
been working in
        > >RPG/400 V3R1. Please let me know some good sites or books
available in the
        > >market.
        > 
        > Any books by Bryan Meyers are highly recommended. Also, check
out both MC
        > and NEWS website, at least one (and I think both) have
published
        > RPG/400->ILE RPG converters that do a little more than the
AS/400 converter.
        > 
        > rp
        > 
        > 
        > 
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