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Re: [jboske] Syntactic unambiguity



On Sun, 3 Aug 2003, John Cowan wrote:

> > How is it that we know that Lojban is syntactically unambiguous?
>
> YACC complains about ambiguities, though it will still cope with them.
> The Lojban grammar reports zero conflicts, so it is unambiguous,
> EXCEPT for the various hacks put in

Do we know what these hacks are?

> to keep YACC from spotting places where 1-token lookahead isn't enough.

I was of the belief that iff YACC is a LALR(1) parser, then it can't cope
with more than 1-token lookahead. Why are we writing rules for it that
requires more than 1-token lookahead?

> Ambiguities can lurk there, and have to be searched for by hand.

That is very disturbing. I hope those hacks are only a few, so that we can
have a hope of *proving* the grammar to be unambigous.

-- 
Arnt Richard Johansen                                http://arj.nvg.org/
Jeg er nok verdens sydligste sengev�ter. Forutsatt at ingen p� basen p�
Sydpolen driver med slikt, da.        --Erling Kagge: Alene til Sydpolen