[antlr-interest] Re: Nondeterminism problem

[Terence Parr]

On Sunday, December 14, 2003, at 11:51 AM, sarah2geller wrote:
>> Part of my confusion is that SLL(k) subset LALL(k) subset LL(k).  I
>> cite pg 233 of "Parsing Theory II" by Sippu and Soisalon-soininen,
>> Spring-Verlag 1990: "For k>1, the class of SLL(k) grammars is
> properly
>> contained in the class of LALL(k) grammars...".  PCCTS did/does LALL
> (k)
>> and thus can generate a larger class of languages than SLK.  Can
> you
>> clear up my misunderstanding?
>>
>
> But for what maximum value of k, and in what time?

That's not my question.  Your claim contradicts well-established 
parsing theory...how do you respond?

> Why the nondeterminism in the grammar that is strong LL(2)?

Because antlr 2 only does approximate LALL(k) not full LALL(k), but 
PCCTS (antlr 1) did full LALL(k) and antlr 3 (coming soon to a theatre 
near you) will do that plus LL-regular.

Your SLK is weaker than PCCTS's LALL(k)...just wanted to clear that up. 
  You make some dubious claims on your site and I find your anonymity 
highly curious.

Best regards,
Terence
--
Professor Comp. Sci., University of San Francisco
Creator, ANTLR Parser Generator, http://www.antlr.org
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