Re: [BLACKBOX] Re [BLACKBOX] Seasons Greetings from Linuxland

From: Rene A. Krywult <"Rene>
Date: Tue, 28 Dec 2010 09:31:45 +0100

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Talking about languages "encouraging good or bad code".

First of all, a programming language *is* a language, and thus it is possible to have a good style or a bad style, just as with a natural language.

But second, there are *some* examples I really like to share.

The first two come from PL/1, a language I had to use a lot on IBM3270:

1)
PROCEDURE TEST;
   DCL A,B,C BIN FIXED(31)
   A=0;
   B=1;
   C=1;
   RETURN(A=B=C)
END;

I think this is problem inherent in the language, and not so much a question of bad style. Someone who has PL/I as a first language will, when switching to C, naturally write unreadable code when trying to do the same as above, while a Wirthian language will force him to do better.

2)
IF XY=1 THEN;
ELSE GOTO A;
   .
   .
   .
A:
   .
   .

where A is not used for anything else than the one (!) goto above, and XY is also only set once (but depending on a condition). The points between GOTO A; and A stand for various statements, as do the points after A:

These are real-life examples I encountered myself when working for a supermarket chain about 16 years ago. Example 2 was in a central program. There were about 50 such statements in the program, no procedures and functions at all. The program ran once a month, every month it crashed, and it took the original programmer about 1 week each month (with 10 hour working days!) to "fix" the bug. Then he had a heart attack, and I, a newcomer to PL/I had to take over.....

What I'm saying is: You can write good style and bad style in any language, but with a compiler that forces you to not commit the ugliest style-errors, you do not need so much of a style guide, and you are trained to think and write more clearly.

A friend of mine, chief software engineer in a bank and a very intelligent guy, told me, that it took him 5 years to find a good style for C++, and then he wrote a style guide for the bank, where he hoped that everybody used it.

Rene


 
-------- Original-Nachricht --------
> Datum: Mon, 27 Dec 2010 19:41:56 -0500
> Von: Wojtek Skulski <skulski{([at]})nowhere.xy
> An: BLACKBOX{([at]})nowhere.xy
> Betreff: Re: [BLACKBOX] Re [BLACKBOX] Seasons Greetings from Linuxland

> > The following hypothetical examples are intended to show what a
> programmer
> > could concoct if he has muddled thinking regarding boolean logic [snip]
>
> My own conclusion is that one can write C in any language. One also can
> write reasonable code in C. Some languages encourage good attitude while
> others just the opposite, but at the end of the day it is the attitude,
> which differentiates the masters from their opposites.
>
> Playing devil's advocate, I remember my utter surprise when I read
> statements in Project Oberon like "IF mouse = 1 THEN...". The mouse keys
> were numbered 1,2,3 (or 0,1,2, don't remember) and these numbers were used
> literally in the code published in the book (!!). A bit shameful, was it
> not? In later versions the literal constants we replaced with ML, MM, and
> MR, as they should have been from the beginning.
>
> Even our gurus have had their bad days.
>
> W.
>
>
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Received on Tue Dec 28 2010 - 09:31:45 UTC