Release:
========

This package contains the XPathReader class for accessing document 
elements via XPath in C++. This package uses libxml -- you need to 
get a good recent version (I use 2.5.1).

Configuration
=============

GNU autoconf / automake style configuration. You need to provide the
location of the libxml2 installation using the --with-libxml2=<dir>
option to configure:

eg: (for me on the Edinburgh Physics machines)

./configure --with-libxml2=/Home/bj/Devel/SciDAC/install/libxml2

then type 

gmake 

to make the library.

gmake install

to install as usual.

Running: 

gmake check

will build the examples in the examples/ directory.

Documentation
=============
 Almost as much as for libxml :) (or should that be :( )
I have added excessive comments to the header files:
  basic_xpath_reader.h

and 
 
  xpath_reader.h 

in the include directory, at the start of the files. I recommend
you read them.

Examples
========

I provide 3 examples in the examples directory:

i) basic_xpath_reader_test 
--------------------------

This is effectively an XPath shell. 
Run:      basic_xpath_reader_test foo.xml

and type XPath expression. 

Typing / should return the whole document.

ii) basic_xpath_reader_test2
----------------------------

This actually tries to get at bits of the XML and store them in
variables/classes. THe output should produce a bunch of failure
and success messages (it contains deliberately erroneous queries)

iii) xpath_reader_test2
-----------------------

Much like basic_xpath_reader_test2 but using the full XPathReader.
Also matches some weird types like complex'es and arrays etc.

Conformance
===========

XML:	I use libxml2 and this sets an upper limit on my standard
        conformance. I then deal probably dodgily with namespaces.
	(see www.xmlsoft.org for details of libxml2 conformance)

C++:    I make pervasive use of ANSI standard io and string streams 
        I also make use of templates a great deal, but hopefully 
	only in ANSI/ISO C++ ways.

	My code compiled with g++-3.2 -- 'nuff said.
	(earlier eg g++-2.x series compilers may barf).

Future
======

immediate/near: 

   Some kind of writer class API, so we can write as well as read.

intermediate/medium distant:

   Autogeneration of unmarshal (read?) functions from some kind 
of mapfile, which contains XPath (perhaps a sophisticated XSLT?).
This could be done by PERL/Python. The source for unmarshalling
would use XPathReader...

far/distant/perhaps never:
    Autogeneration of the mapping file by reading XMLSchema
	=> Complete C++ Open Source Data Binding Framework.