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From: abcscagz@csuna.UUCP (stepanek/cs assoc)
Newsgroups: comp.lang.modula2,comp.lang.c
Subject: "for" loops (was Re: C++ vs. Modula2)
Message-ID: <1611@csuna.UUCP>
Date: 26 Jan 89 01:45:52 GMT
References: <INFO-M2%89011219330825@UCF1VM> <739@jupiter.iis.UUCP>
Reply-To: abcscagz@csuna.csun.edu (Jeff Boeing)
Organization: California State University, Northridge
Lines: 39

In article <739@jupiter.iis.UUCP> heiser@iis.ethz.ch (Gernot Heiser) writes:
>
>worst features. C's 'for' is really a 'while' with an initialization clause and
>a designated spot that may contain an incrementation clause. What I consider a
>"real" 'for' (as opposed to the while/repeat/loop family) is a construct that
>executes a specific number ot times, the iteration count being determined
>BEFORE the processing of the body starts. This is what is really needed most of
>the time in numerical programs. The other cases are exactly what while/repeat/
>loop constructs are for.


Actually, C's "for" can be duplicated EXACTLY by C's "do ... while" loops.
Consider:

    for (i = 0; i <= 17; ++i)
    {
        stuff();
        more_stuff();
    }

versus:

    i = 0;
    do {
        stuff();
        more_stuff();
    } while (++i <= 17);


These two iterations are indistinguishable from one another.  The "for" term
in C is totally superfluous and is only included because it makes it look like
languages that have a more "for"-ish "for" statement, like Pascal or Modula.
(I won't even get into Algol's "for" here....)

-- 
Jeff Boeing:  ...!csun.edu!csuna!abcscagz    (formerly tracer@stb.UUCP)
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