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From: peirce@outpost.UUCP (Michael Peirce)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Pascal deficiency?
Message-ID: <0B010004.kmq00z@outpost.UUCP>
Date: 17 Dec 90 23:09:02 GMT
Reply-To: peirce@outpost.UUCP
Organization: Peirce Software
Lines: 36
X-Mailer: uAccess - Mac Release: 1.0.3


In article <q72au3w163w@questor.wimsey.bc.ca>, aberno@questor.wimsey.bc.ca (Anthony Berno) writes:
> 
> I generally prefer Pascal programming, but I have come up against what
> seems like a real deficiency in the language. I never really thought
> about it before, but there does not seem to be any equivalent to
> the ++ or -- operator in Pascal. I was doing some speed checks on
> array accessing today, and it occured to me that in doing something
> like incrementing an entry by one, the computer was doing rather a
> lot of work!
> 
> Either there is no way to do a quick increment in Pascal, or I'm missing
> something in my knowledge, or I'm wrong about the speed difference between
> things like
> ++(variable) and
> (variable):=(variable)+1
> 
> Any comments? This is pretty basic, I know, but I never considered it
> before. :)  Excuse me while I go get my asbestos suit on.

Using X := X + 1; rather than the c style X++; is more a matter of style 
than substance.  Just to make sure I Iooked at the code generated from a 
"X := X + 1;" statement (using DUMPOBJ in MPW) and found the use of 

"ADDQ.W  #$1,-2(A6)".  

The same instruction was generated by C for both "X++;" and "X = X + 1;" too.

Don't worry, be happy.  Pascal does a pretty good job for you.

-- michael


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