Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!ames!pasteur!ucbvax!agate!shelby!csli!jkl
From: jkl@csli.Stanford.EDU (John Kallen)
Newsgroups: comp.lang.c
Subject: Re: Pointer incrementation and assignme
Message-ID: <9135@csli.Stanford.EDU>
Date: 27 May 89 05:51:56 GMT
References: <2015@csuna.csun.edu> <236100012@mirror>
Sender: jkl@csli.Stanford.EDU (John Kallen)
Reply-To: jkl@csli.stanford.edu (John Kallen)
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In article <236100012@mirror> root@mirror.TMC.COM writes:
>In reality
>the command a++ is just shorthand for a+=1 and a = a+1.  It was origionally
>made for lines like:
>
>	whatchamacallit = whatchamacallit + 1;
>
>Carnigan and Ritchie were programmers who didn't like to type.

Kernighan and Ritchie might be lazy typists, but there's another for
having += and ++ operators: I don't have it in front of me, but in the
Bible there was an example of a hairy expression like:

	yylval[yylval1[i]][yylval2[i]] = yylval[yylval1[i]][yylval2[i]] + 1;

which might very easily get corrupted inadvertently. Now,

	yylval[yyval1[i]][yylval2[i]] ++;

is not only shorter code, but *safer*, and above all MUCH clearer.
Useful little beasties, the assignment and the increment operators.

John.
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