From: cbmvax!uunet!math.ucla.edu!jimc
Message-Id: <9105311612.AA23157@luna.math.ucla.edu>
To: lojban-list@snark.thyrsus.com
Subject: MEX comments
Date: Fri, 31 May 91 09:12:49 -0700
Status: RO

John Cowan's MEX posting didn't get much comment recently.  I had very
few nits to pick with it, except for one example (most likely a typo) 
where something of the form "re ratcu" seemed to be interpreted as a
sumti (should be "le re ratcu" (the two rats) or "re le ratcu" (two of
the rats)).  I would say that it is quite serviceable for Lojban.

I will leave it to others to wrangle over RPN vs. infix notation, and
whether it's tolerable to demand exactly two operands per operator
(with fancy escape kludges).  Gua!spi uses the base grammar, with no
special MEX syntax.  Because -gua!spi segregates phrase-grouping
grammar from everything else, it can handle intermixed RPN, forward
Polish, and infix, with any number of operands, with no markings and no
parentheses.  Actually the mandatory phrase specifications imported
from the grammar are equivalent to full explicit parenthesization. 
Flame one at a time, please :-)

There are a few points that I would like to see treated in more detail.
First, what does "the number two" mean?  Second, what is the most 
convenient way to assert that the measure of something is given by some
MEX?  In -gua!spi, all the math operators mean "x1 is in the
equivalence class resulting from doing (math) on arguments x2...", so
predication is trivial, and the answer as a number can be recovered
with [the -gua!spi equivalent of] lo'i "set of referents fitting
s-bridi". Third, dimensioned quantities are common; how are they to be
defined and expressed?  In -gua!spi: "x1 is in the equiv class of things
which are x2 meters in size", a normal gismu.

I would remind people of an essay on MEX that I posted about a year ago.
Turns out it's archived:  send a message that says "send guaspi/mex-guaspi"
to langserv@ivory.cc.columbia.edu.  It has more detail on these points
plus a translation challenge.

		-- jimc