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From: preston@titan.rice.edu (Preston Briggs)
Newsgroups: comp.lang.misc
Subject: Re: What I'd really like to see in an if-statement...
Message-ID: <516@brazos.Rice.edu>
Date: 10 Aug 89 18:54:34 GMT
References: <8577@batcomputer.tn.cornell.edu> <14251@haddock.ima.isc.com>
Sender: root@rice.edu
Reply-To: preston@titan.rice.edu (Preston Briggs)
Organization: Rice University, Houston
Lines: 56

In article <14251@haddock.ima.isc.com> 
>	karl@haddock.ima.isc.com (Karl Heuer) writes:
>	...	 You simply add a new production rule
>which parses "a < x < b" as a ternary operator, 
>and produce code equivalent to
>	evaluate x into temp
>	compare a with temp
>	jump-if-ge FALSE-BRANCH
>	compare temp with b
>	jump-if-ge FALSE-BRANCH
>Generating the temporary is trivial for a compiler; 
>it's not as if this had to
>be parsed by a macro preprocessor.
>
>The lookahead to distinguish the constructs "E < E < E" and "E < E" is, I
>believe, no worse than the problem of distinguishing "if (E) S;" and
>"if (E) S; else S;".

But you wouldn't want a single production to get a