Xref: utzoo comp.lang.modula2:1247 comp.lang.c:15918
Path: utzoo!utgpu!watmath!clyde!ima!cfisun!lakart!dg
From: dg@lakart.UUCP (David Goodenough)
Newsgroups: comp.lang.modula2,comp.lang.c
Subject: Re: "for" loops (was Re: C++ vs. Modula2)
Message-ID: <405@lakart.UUCP>
Date: 30 Jan 89 16:28:15 GMT
References: <1611@csuna.UUCP>
Organization: Lakart Corporation, Newton, MA
Lines: 48

From article <1611@csuna.UUCP>, by abcscagz@csuna.UUCP (stepanek/cs assoc):
> 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);

Yes, but how about:

	for (i = 0; i <= a; i++)
	 {
	    lots_of_stuff();
	 }

against:

	i = 0;
	do
	 {
	    lots_of_stuff();
	 } while (++i <= a);

when the value of a is (say) -5. Are you _SURE_ these two are the same?

Better would be to say a for loop can be replaced by a while loop:

	i = 0;
	while (i <= a /* or 17 */)
	 {
	    lots_of_stuff();
	    i++;
	 }
-- 
	dg@lakart.UUCP - David Goodenough		+---+
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