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From: bowles@cbosgd.UUCP (Jeff Bowles)
Newsgroups: net.lang.c
Subject: Re: Arcane C hacks?
Message-ID: <1836@cbosgd.UUCP>
Date: Tue, 18-Feb-86 22:42:08 EST
Article-I.D.: cbosgd.1836
Posted: Tue Feb 18 22:42:08 1986
Date-Received: Thu, 20-Feb-86 01:32:48 EST
References: <1700003@umn-cs.UUCP>
Reply-To: bowles@cbosgd.UUCP (Jeff Bowles)
Organization: AT&T Bell Laboratories, Columbus
Lines: 35

(Gee, wasn't the article I'm replying to supposed to be here, too?)

Well, anyway, the article I'm following up is one where a programmer
asks why:
	int i;
	...
	goto labels[i];	/* "levels" contains pointers to, well,
			 * you get it...
			 */
went away from C. [I guess it used to be valid. Hmmmm.]

If you feel the need to do something like this, you probably want
to just use a structure:
	struct bletch {
		int	l_token;	/* If you see this, */
		void	(*l_whither)();	/* then call this routine */
	};
Then you can just do a table lookup, calling the appropriate
routines for each item.

Or, :-), you can use the "computed goto" that C provides:
	switch (i) {
		case 0:
			...
			break;
		case 1:
		...
		}
The "table lookup" that C provides will usually do what you
need, with minimal effort. If you're translating an assembler
program and need to "jump to the location specified by the N'th
element of this array", I suggest finding a BCPL compiler.

	Jeff Bowles
	Lisle, IL