[Libxmlplusplus-general] SAX 2 support

[Edd D. <ed...@us...>]

Hi there

libxml++ doesn't have a SAX2 API, which is really the baseline API for
stream parsing these days.  The most important thing it buys the user is
support for XML namespaces.

The question is how to implement this.  libxml has no direct support for
namespaces in its SAX API.  The file SAX.c in libxml is an actual
implementation of namespaces, so some of that code could be used.

It is possible to write a SAX2 API by layering on the SAX one.

http://www.saxproject.org/?selected=3Dsax2 shows the changes from SAX1 to
SAX2 (read from the bottom up).  Aside from namespace support the major
feature additions are SAX filters, which can sit in the event stream and
filter data, and "features and properties", mechanisms for controlling
parser behaviour.

There's already a BSD-licensed wrapper for libxml that provides SAX2,
http://www.jezuk.co.uk/cgi-bin/view/arabica, but of course that's not
GPL.

Perhaps the most useful starting point could be the ParserAdapter class
-- see
http://www.saxproject.org/apidoc/org/xml/sax/helpers/ParserAdapter.html

This is a class that layers on a SAX parser to make it a SAX2 one.  The
license says "public domain" so I've no idea what the licensing status
of a direct port to C++ would be. http://www.saxproject.org/?selected=3Dpd

-- Edd