Re: revisiting a prgramming problem

From	Paul E Bennett <Paul_E.Bennett@topmail.co.uk>
Newsgroups	comp.lang.forth
Subject	Re: revisiting a prgramming problem
Date	2014-12-02 11:53 +0000
Organization	Hidecs Consultancy
Message-ID	<ce5nh9Fl2pU1@mid.individual.net> (permalink)
References	(5 earlier) <m2blr1$m7c$1@dont-email.me> <1542736d-0bc5-404a-9481-c38ae60c394b@googlegroups.com> <m5dsjk$ptj$2@dont-email.me> <766ef7c8-49ad-4d97-8e50-1beb89b7d673@googlegroups.com> <m5jqqk$dk6$1@dont-email.me>

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rickman wrote:

> On 12/2/2014 1:43 AM, the_gavino_himself wrote:
>> On Saturday, November 29, 2014 8:41:24 PM UTC-5, rickman wrote:
>>> On 11/9/2014 12:33 AM, the_gavino_himself wrote:
>>>> On Thursday, October 23, 2014 12:44:40 PM UTC-7, rickman wrote:
>>>>> On 10/21/2014 4:18 PM, Hans Bezemer wrote:
>>>>>> Paul Rubin wrote:
>>>>>>
>>>>>>> Hans Bezemer <the.beez.speaks@gmail.com> writes:
>>>>>>>> Duh.. : sumofsquare over max dup * >r max dup * r> + ;
>>>>>>>
>>>>>>> 1 2 3 sumofsquare . 13  ok
>>>>>>> 2 3 1 sumofsquare . 18  ok
>>>>>> Darn, that was the only iteration I didn't test ;-)
>>>>>> Back to the drawing board!
>>>>>
>>>>> Not trying to pick on anyone, but this illustrates the fallacy of
>>>>> testing to prove the absence of errors.

There are four aspects to getting Forth Words (and code generally)  to 
perform exactly as it is specified to do so.

1. Write the glossary definition first (before coding) and ensure that it 
states explicitly what you want to happen in clear and un-ambiguous terms. 
Note any limitations you may accept from the code.

2. Perform a thorough Fagan Style Inspection (Intense Static Analysis) that 
checks the code is likely to perform as expected, following the down to 
ensure that called words are used as they expect to be used (right numbr of 
parameters on stack in the appropriate order).

3. Perform a Functional Test to make sure it does as you expect (including 
ensuring you follow every path within the code).

4. Use your imagination to concoct tests that aim to destroy the confidence 
you have in the code you have produced. Better yet, ask someone else to try 
and make it fail (noting fails within its stated limits).

If the above code was meant to have done what I thought it should have done 
(ie:- sum the squares of each of the numbers presented), both tests of it 
failed as both should have returned 14 as the answer. However, as the intent 
wasn't really stated it is hard to be sure if even my guess based on the 
word name is the relevant interpretation.

If it is as I suspect then I probably would have factored out the squaring 
operation and simplified the stack management to make it very clear what was 
going on.

-- 
********************************************************************
Paul E. Bennett IEng MIET.....<email://Paul_E.Bennett@topmail.co.uk>
Forth based HIDECS Consultancy.............<http://www.hidecs.co.uk>
Mob: +44 (0)7811-639972
Tel: +44 (0)1235-510979
Going Forth Safely ..... EBA. www.electric-boat-association.org.uk..
********************************************************************

Thread

revisiting a prgramming problem gavino_himself <visploveslisp@gmail.com> - 2014-10-14 15:55 -0700
  Re: revisiting a prgramming problem hughaguilar96@yahoo.com - 2014-10-14 18:52 -0700
    Re: revisiting a prgramming problem Hans Bezemer <the.beez.speaks@gmail.com> - 2014-10-21 17:58 +0200
      Re: revisiting a prgramming problem Paul Rubin <no.email@nospam.invalid> - 2014-10-21 09:09 -0700
        Re: revisiting a prgramming problem Hans Bezemer <the.beez.speaks@gmail.com> - 2014-10-21 22:18 +0200
          Re: revisiting a prgramming problem rickman <gnuarm@gmail.com> - 2014-10-23 15:44 -0400
            Re: revisiting a prgramming problem "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-10-23 17:01 -0400
            Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-08 21:33 -0800
              Re: revisiting a prgramming problem rickman <gnuarm@gmail.com> - 2014-11-29 20:40 -0500
                Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-12-01 22:43 -0800
                Re: revisiting a prgramming problem rickman <gnuarm@gmail.com> - 2014-12-02 02:47 -0500
                Re: revisiting a prgramming problem Paul E Bennett <Paul_E.Bennett@topmail.co.uk> - 2014-12-02 11:53 +0000
                Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-12-02 05:23 -0800
                Re: revisiting a prgramming problem rickman <gnuarm@gmail.com> - 2014-12-02 09:01 -0500
        Re: revisiting a prgramming problem Hans Bezemer <the.beez.speaks@gmail.com> - 2014-10-21 22:25 +0200
          Re: revisiting a prgramming problem Paul Rubin <no.email@nospam.invalid> - 2014-10-21 16:10 -0700
            Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-08 21:41 -0800
        Re: revisiting a prgramming problem Hans Bezemer <the.beez.speaks@gmail.com> - 2014-10-21 22:30 +0200
          Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-12-01 22:45 -0800
        Re: revisiting a prgramming problem Hans Bezemer <the.beez.speaks@gmail.com> - 2014-10-21 23:04 +0200
      Re: revisiting a prgramming problem Mark Wills <markwills1970@gmail.com> - 2014-10-21 10:17 -0700
        Re: revisiting a prgramming problem "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-10-22 02:13 -0400
          Re: revisiting a prgramming problem Paul Rubin <no.email@nospam.invalid> - 2014-10-21 23:26 -0700
            Re: revisiting a prgramming problem "Alex McDonald" <blog@rivadpm.com> - 2014-10-22 16:18 +0100
              Re: revisiting a prgramming problem mhx@iae.nl (Marcel Hendrix) - 2014-10-22 21:27 +0200
                Re: revisiting a prgramming problem albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-24 10:30 +0000
                Optimal comparisons for m maximums from n items  (was Re: revisiting a prgramming problem) "Alex McDonald" <blog@rivadpm.com> - 2014-10-24 16:29 +0100
                Re: Optimal comparisons for m maximums from n items  (was Re: revisiting a prgramming problem) albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-25 08:27 +0000
                Re: Optimal comparisons for m maximums from n items (was Re: revisiting a prgramming problem) "Alex McDonald" <blog@rivadpm.com> - 2014-10-25 18:54 +0100
                Re: revisiting a prgramming problem mhx@iae.nl (Marcel Hendrix) - 2014-10-25 13:28 +0200
                Re: revisiting a prgramming problem mhx@iae.nl (Marcel Hendrix) - 2014-10-25 14:28 +0200
                Re: revisiting a prgramming problem mhx@iae.nl (Marcel Hendrix) - 2014-10-25 15:17 +0200
            Re: revisiting a prgramming problem Gerry Jackson <spam@qlikz.org> - 2014-10-22 21:57 +0100
              Re: revisiting a prgramming problem Paul Rubin <no.email@nospam.invalid> - 2014-10-22 14:06 -0700
                Re: revisiting a prgramming problem Bernd Paysan <bernd.paysan@gmx.de> - 2014-10-23 00:03 +0200
                Re: revisiting a prgramming problem albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-23 14:46 +0000
                Re: revisiting a prgramming problem Paul Rubin <no.email@nospam.invalid> - 2014-10-23 08:16 -0700
                Re: revisiting a prgramming problem "Alex McDonald" <blog@rivadpm.com> - 2014-10-23 19:21 +0100
                Re: revisiting a prgramming problem "Alex McDonald" <blog@rivadpm.com> - 2014-10-23 20:02 +0100
                Re: revisiting a prgramming problem albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-10-23 20:29 +0000
                Re: revisiting a prgramming problem Coos Haak <chforth@hccnet.nl> - 2014-10-23 22:23 +0200
              Re: revisiting a prgramming problem awegel@arcor.de (Alexander Wegel) - 2014-10-23 00:36 +0200
                Re: revisiting a prgramming problem Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2014-10-24 10:44 +0100
              Re: revisiting a prgramming problem hughaguilar96@yahoo.com - 2014-10-22 17:26 -0700
                Re: revisiting a prgramming problem Michael Barry <barrym95838@yahoo.com> - 2014-10-23 00:02 -0700
          Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-08 23:10 -0800
        Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-08 21:42 -0800
  Re: revisiting a prgramming problem Roger Levy <roger.levy@gmail.com> - 2014-10-15 08:18 -0700
    Re: revisiting a prgramming problem Roger Levy <roger.levy@gmail.com> - 2014-10-15 08:18 -0700
      Re: revisiting a prgramming problem november.nihal@gmail.com - 2014-10-15 08:57 -0700
      Re: revisiting a prgramming problem Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2014-10-15 17:10 +0100
      Re: revisiting a prgramming problem "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-10-17 21:53 -0400
    Re: revisiting a prgramming problem Roger Levy <roger.levy@gmail.com> - 2014-10-15 08:19 -0700
  Re: revisiting a prgramming problem awegel@arcor.de (Alexander Wegel) - 2014-10-22 00:30 +0200
    Re: revisiting a prgramming problem hughaguilar96@yahoo.com - 2014-10-21 16:07 -0700
      Re: revisiting a prgramming problem awegel@arcor.de (Alexander Wegel) - 2014-10-22 03:23 +0200
        Re: revisiting a prgramming problem "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-10-22 02:15 -0400
          Re: revisiting a prgramming problem awegel@arcor.de (Alexander Wegel) - 2014-10-22 12:52 +0200
        Re: revisiting a prgramming problem hughaguilar96@yahoo.com - 2014-10-22 17:19 -0700
          Re: revisiting a prgramming problem awegel@arcor.de (Alexander Wegel) - 2014-10-23 16:10 +0200
      Re: revisiting a prgramming problem "Rod Pemberton" <buzzoff@nonamewhichexists.cmm> - 2014-10-22 02:14 -0400
      Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-08 23:21 -0800
      Re: revisiting a prgramming problem "WJ" <w_a_x_man@yahoo.com> - 2014-12-06 02:34 +0000
      Re: revisiting a prgramming problem "WJ" <w_a_x_man@yahoo.com> - 2014-12-27 08:00 +0000
        Re: revisiting a prgramming problem Mark Wills <markwills1970@gmail.com> - 2014-12-27 05:15 -0800
  Re: revisiting a prgramming problem "WJ" <w_a_x_man@yahoo.com> - 2014-11-29 17:20 +0000
    Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-11-29 12:00 -0800
    Re: revisiting a prgramming problem "WJ" <w_a_x_man@yahoo.com> - 2014-12-02 16:15 +0000
  Re: revisiting a prgramming problem Paul Sephton <prsephton@gmail.com> - 2014-12-02 05:06 -0800
    Re: revisiting a prgramming problem Paul Sephton <prsephton@gmail.com> - 2014-12-02 05:14 -0800
    Re: revisiting a prgramming problem the_gavino_himself <visphatesjava@gmail.com> - 2014-12-02 05:24 -0800

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