[lojban] Re: Official parser problem?

[Robin Lee Powell <lojban-out@lojban.org>]

On Thu, Mar 18, 2004 at 12:59:12AM -0500, John Cowan wrote:
> Robin Lee Powell scripsit:
> 
> > In linear time.
> > 
> > Memory usage is a bit bad, but whatever.
> 
> I'll bet: in order to be LR(\infty) equivalent, it has to keep the
> whole stream of tokens available for traversal in both directions.  Be
> it so: this isn't the age of 640K any more.

Indeed.

> > [2]: Actually, without an extension to PEGs, 'zoi' cannot be handled
> > without a pre-processor, and without a re-definition that is at
> > least marginally sane, 'sa' doesn't even have a working definition
> > to try to handle.
> 
> The definition of "sa" is straightforward: check the selma'o of the
> next token rightward, and remove tokens leftward until a token of the
> same selma'o has been removed (in the usual extended sense of
> "selma'o").

<blink>

Oh!

Heck, I can do that *now*.  I'll fix 'si' first, though.

> > [3]: OK, well, I *could* replicate current behaviour, but as current
> > behaviour is based on the technical limitations of YACC and does
> > not, for example, resemble what is described in the book, why would
> > I do that?
> 
> By all means.   All of this stuff is *extremely* borderline behavior.
> 
> Are you using Rats?

Yep.  Couldn't get Pappy to work.

I wish either of them had a mode where they would automagically
generate a parse tree.  Rats!'s debug mode is pretty close, though.

-Robin

-- 
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