Subject: Parsing "na ku" and "na" followed by other things

From: Richard Curnow <[email-masked]>
Date: Tue, 8 May 2001 22:27:21 +0100

I've had a bug report for jbofi'e which identifies an incompatibility
with the 'official' parser. This seems to be the version that targets
v2.33 of the Lojban grammar. [I am not aware of any publically visible
source code for an 'official' parser for v3.00 of the grammar.] 

The example is

i mi djica le nu le nu pensi na zekri

which parses on the 'official' parser, but not on jbofi'e. The problem
has, I think, been discussed at least once on this list - it's that the
word "na" is shifted as though "na ku" is coming, rather than the bridi
"pensi" being reduced first.

I've looked into how the official parser handles this, and it looks like
there's some special logic to recognize "na ku" as a special case, as
though it's a single token (hence the LALR(1) mechanism in the parser
doesn't get confused and shift "na" wrongly. Hence "na" followed by
something else would cause the bridi "pensi" to be reduced in the
example.)

Is this handling of "na ku" considered current behaviour for the v3.00
Lojban grammar? I'm asking because the official parser's behaviour for
this case was never discussed when the "na ku" issue was discussed on
the list before.

I want to go ahead and fix jbofi'e for this case, but obviously only if
detecting "na ku" as though it's a single token is still considered
correct behaviour in grammar v3.00.

-- 
Richard P. Curnow, Weston-super-Mare, UK
http://www.rrbcurnow.freeuk.com/
email:[email-masked] email:[email-masked]