Re: DOW vs DOU- Ha -- MIDRANGE-L


Re: DOW vs DOU

David, I mean Mr. Phelps

<THANK YOU,  Checkmate>

Sorry but your whole mission impossible team was destroyed by just one
of the benign looking but deadly DOW traps. (Now gather round boys and 
girls there is a valuable lession here) 

Mr. Phelps wrote;

>Like this, you mean?
>
>  KEY       CHAINFILEXXX              90

>  *IN90     DOWEQ*OFF
>  XXCODE    ANDNE'B'

>  XXCODE    IFEQ 'A'
>            ITER
>            ENDIF

> <.... whatever process ....>

>  KEY       READEFILEXXX                  90
>            ENDDO


Whats wrong with this Code?  Look at it carefully.

If this code is actually run and the program incounters a XXXCODE = A from 
FILEXXX what you will notice is;

First the lights will dim,  and peoples tubes will seem to freeze,
and you may not have enough resources to kill this job.  BECAUSE.....
the ITER opcode branchs TO the ENDDO statement and by passes the READE
opcode.  Then with lighting speed it will branch back up to the DOW
statement and test the XXXCODE again, It will still be "A" and the process
will continue.  The whole program will be PAGED out except for this chunk 
of code and the machine will get Real Good, Real Fast at executing those 4
statements.

You in essence have a classic example of an INFINITE LOOP! 
The bottom line is that you CANNOT USE an ITER opcode with the DOW!

Other than that your code does, how did you say it; "My example matches
the structure of the code to the structure of the data, whereas yours
 doesn't.".  

That may be true but mine did have Brevity, and it had Clarity, 
and Succinctness, AND it didn't get into an Infinite Loop.  

In the world of Left hand indicators, GOTO/CAB's and spaghetti code,etc.
our lofty discussions of "What is Structured Code" often gets drowned 
out by production deadlines, Byzantine standards, and the rest.  

As some french guy said of goverments "Of forms of goverments, let fools
contest, that which is best adminstered is best"  I believe it's true
of Code as well. Maintainability is #1.

Respectfully 

John P. Carr CDP
EdgeTech 
74711.77@compuserve.com 804-739-7689

P.S. I'd like to meet you 3d sometime and have a beer. DOW aside I still
     Highly respect your opinions!
thanks for the fun

------------------------------------------------------------------
On May 25 1997 John P. Carr wrote:

>Ok David; (Mr Phelps)
>
>Here's your assignment if you chose to accept it, Convert the following
>code of that infamous DOU connoisseur guy  John Carr to a DOW.

>Your score will be judged on Clarity, Brevity, and Succinctness.
>To be especially harsh you cannot code the same IF statement
>twice(But then, why should you need to?).


>  KEY      SETLL  FILEXXX
> *IN90     DOUEQ  *ON
>  KEY      READE   FILEXXX                 90
> *IN90     IFEQ   *ON
>           LEAVE
>           ENDIF
>
>  XXXCODE  IFEQ    'B'
>          LEAVE
>          ENDIF
>
>  XXXCODE  IFEQ     'A'
>           ITER
>           ENDIF
>< ... end of in-line edits ...>
>
> <.... whatever process ....>
>
>          ENDDO


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