From: cbmvax!uunet!mullian.ee.mu.OZ.AU!nsn
Message-Id: <9104110825.12552@mullian.ee.mu.OZ.AU>
To: lojban-list@snark.thyrsus.com
Cc: nsn@mullian.ee.mu.oz.au
Subject: Elision, or: Nick rides again in jbonai
Organisation: Department of Electrical Engineering, University of Melbourne
Smiley-Convention: %^)
Date: Thu, 11 Apr 91 18:25:02 +1000
Status: RO


From: Guy Steele <gls@Think.COM>
   From: cbmvax!snark.thyrsus.com!cowan@uunet.UU.NET (John Cowan)
   loop!dont@tessi.uucp (Don Taylor) writes:

^   The elidable terminators make the language unambiguous, but may often be
^                                              ^^ ????????
^Did you mean "ambiguous"?

No he does not. Whatever do you mean, Guy? The terminators are there to
denote the end of phrase-sections corresponding to BNF nonterminals. What
is ambiguous about {vau}, {be'o} or {ku'o}? Or am I missing a smiley here?

^Hm.  It seems to me that if the "official" grammar allows such elision
^in practice, then it behooves the language definers to produce a more
^elaborate grammar that takes this into account, if it can be done using
^a context-free grammar.  But if the resulting grammar is context-sensitive,
^then allowing such elision may be a bad idea in the first place.

Think again. In JL13, lojbab's YACC has no problem in filling in the
missing terminals. As for what the grammar allows or disallows - my God,
have you actually ever written an lojban sentence?! There is no need
to dot every i and cross every chicken across the road. A language in
which I'd have to put in {ku} after every single damn sumti is a language
I would not stick around in. In {le klama le seklama cu klama}, it is
fairly obvious to me (and I don't really think it needs codifying) that
{le klama} and {le se klama} are two distinct sumtis, and that starting
a new sumti with {le} means the old sumti must have finished (elided {ku}).

I don't know enough about parsing to tell whether the BNF handles such
elisions as well as did the YACC: JC's presentation of what should be 
obvious was admittedly handwaving a bit. But people have no problem with
elision, and machines have no major problem with it either, so where's
the problem? However handwaving rule 10 was (and all you've got to do
is read five lines of lojban to realise that it doesn't really matter),
JC's BNF is cool. It's a pleasure to be actually able to check through
a structure's validity in half a minute.

^Consider the following seven sentences.
Watch me:

^This sentence no verb.
Grammatically wrong in lojban, because all sentences in it have bridis.
Besides, the 'no' would go with the (non-present) verb, not with the noun
'verb': you are saying that This sentence NOT somethings a verb, not:
this sentence, non-verb.

^Has no subject.
Legit in lojban. Actually, pretty commonplace. lojbab calls 'em observatives.
Get out of English, Guy: subjectless verbs are all over the place (and
they're emulated by impersonals when the language can't handle a missing
subject: 'It rains', 'There's a fire'.)

^This sentence has no.

This is trickery. the 'no' implies syntactically an object which you've
just dropped off. Why don't you try something more honest and less
anglocentric, like 'This sentence has'.

^Has.

'Pluvas'. It rains. 'Estas' There is. (Esperanto. I'd quote Greek, but the
subject is implicit in the conjugation there).

^Object.

Not grammatical in lojbo, unless the object is converted into a bridi by
being prefixed with {me}. The meaning of {me zoi .gic. object .gic.} is
roughly 'there's an object'.

^This sentence.

Ditto. This all has less than nothing to do with the elision of terminators;
you're ommiting thingts you may not in lojban. There is no // around
'bridi' in the 'bridi-tail' rule.

(Yes, I'm rather snappy and irritable. It's just that I'd like to see
someone criticise lojban from within for a change. Not whether we should
have UI words, but which UI words we can drop with impunity. I'm sure
a couple of BAI words won't be missed. Publication of the language is
imminentish - these issues have to be raised by people outside the inner
sanctum. I respect the folks in the inner sanctum and wouldn't mind 
joining them; but I want to make sure they don't get used to the sound
of their own voice.)

{co'ofi'emi'e nitcion}