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* LUG meet on 12 Jan. 2003 @ VJTI
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On Thu, 12 Dec 2002 16:29:08 +0530
Kapil Karekar wrote:

>Congrats Tahir, for the first release of Xqueeze !

Thanks a lot Kapil! Well, I'd have announced this here and on
the PRC list but I'm waiting for the reference implementation to
be uploaded. Some clean-up and source documentation are remaining
and I hope it'll get done in 2 weeks.

Sameer, I'm yet to go through the kuro5hin article but there had
been discussions on XML-Dev[1] about why "binary" XML and other
attempts at reducing the complexity are not acceptable to a
majority. A compilation of this discussion is there on
xml.com[2]. The main reservations that were raised were:

1. Compression adds a computation overhead that may offset any
performance gains

2. Usability of XML tends to get restricted due to these attempts

3. Some of the "compact" formats are more difficult to parse than
XML

4. Even if everything is fine, the performance benefit obtained
may be too insignificant to warrant a switch to the new format.

I can't do much to help point 4. The only thing needed to
switch to xqML is to replace the XML generating and parsing
software with one that generates/parses xqML and nothing gets
changed above (i.e. in software layers).

Though I don't have any benchmarking results, I'm expecting xqML
to parse much faster than XML. I wrote a parser from scratch in 5
hrs and 250 odd lines of C++ code. While parsing XML, a parser
has to look for at least 2 characters (< and &) per character of
input and for PDATA, it has to look for *atleast* 6 characters (<
& > ' " [whitespace chars]). So the number of comparisons
required to parse a document goes up too high. The *max*
comparisons required are 1 in xqML CDATA (<) and 6 for PDATA.
Moreover, the parser knows before-hand where those 6 comparisons
need to be made, so it doesn't spend time doing useless
comparisons.

Point 2 has been taken care of and xqML aims to be XML for all
practical purposes, except in the way it looks.

Point 1 was a seriously valid point IMHO, so I avoided
compression completely. BTW, xqML too yields to compression
nicely, though the "niceness" is proportional to the amount of
CDATA in the file.

[1]
http://lists.xml.org/archives/xml-dev/200104/threads.html#00205

[2] http://www.xml.com/pub/a/2001/04/18/binaryXML.html

PS: Interested people please join the xqueeze-users mailing list:
http://lists.sourceforge.net/lists/listinfo/xqueeze-users

-- 
Tahir Hashmi (VSE, NCST)
http://staff.ncst.ernet.in/tahir
tahir AT ncst DOT ernet DOT in

We, the rest of humanity, wish GNU luck and Godspeed

-- 
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