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From: daveb@geac.UUCP (Brown)
Newsgroups: comp.lang.c
Subject: Re: goto's and switch statements -- mild proposal
Message-ID: <1100@geac.UUCP>
Date: Wed, 12-Aug-87 08:34:59 EDT
Article-I.D.: geac.1100
Posted: Wed Aug 12 08:34:59 1987
Date-Received: Fri, 14-Aug-87 04:10:28 EDT
References: <855@tjalk.cs.vu.nl> <2683@hoptoad.uucp> <916@haddock.ISC.COM> <1032@ius1.cs.cmu.edu>
Reply-To: daveb@geac.UUCP (Dave Brown)
Organization: The little blue rock next to that twinkly star.
Lines: 46
Summary: for C[2] (or P), we can restrict the range of gotos

In article <1032@ius1.cs.cmu.edu> edw@ius1.cs.cmu.edu (Eddie Wyatt) writes:
>In article <916@haddock.ISC.COM>, karl@haddock.ISC.COM (Karl Heuer) writes:
>> In article <2683@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) writes:
>> >What bothers me is that I can't say ["goto default" and "goto case N"].
>> Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint
>
>   Consider the problems "goto case N" cause when there are two switch
>statements each with a case N label in the function block.
>					Eddie Wyatt

  This is NOT a proposal for C (its for P, as in BCPL).
  One should restrict the range of gotos referring to switch/case/whatever
labels to the body of the switch, as in:

	...
	switch (foo) {
	case 'a':
		a(bar);		-- note no fall-through
	case 'f' | 'e':		-- one possible syntax...
		f(foo,bar);
		goto case 'a';	-- another possible syntax
	case DEL:
		goto crash;
	}
	...

	unwind();
	return bar;
 crash: 
	partially_unwind();
	return ERR;


  A "goto case x" outside a switch would be an error.

	--dave

	



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