Wither
======
XML/HTML Generation DSL

Intro
------
Wither is a library designed to make XML generation under python as simple and 
as nicely formatted as python code.

Wither is implemented as a thin stateless wrapper around etree.Element objects 
and works by making use of the 'with' keyword in python to build a nested tree 
of etree objects that can be processed with standard tools/techniques

by using python as a DSL you can automatically ensure that all tags are 
properly closed and also execute arbitrary python code to build things such as 
lists or to embed widgets

Example
--------
>>> import lxml.usedoctest
>>> from wither import Node
>>> n = Node('html')
>>> with n.head as head:
...     head.title == 'Wither README Example'
...     head.link(href='http://code.pocketnix.org/wither', rel='homepage')
<...>
>>> with n.body as body:
...     body.h1 == 'Welcome to the Wither README'
...     with body.div as div:
...         div.p == 'This is the example from the README file'
...         div.p(style='color: red;') == 'Big Red Warning'
<...>
>>> print(n)
Wither README Example
Welcome to the Wither README

This 
is the example from the README file

Big Red 
Warning

Features
---------
* Uses python as a DSL for XML Generation
* Uses/Abuses python syntax to make node generation shorter and more visually 
  appealing
* Uses lxml for document generation
* Possibility to fall back to built in etree implementations (XXX TODO: Write 
  me)
* Easy widget creation
* Implicit verification of document correctness (python's indentation means you 
  cant forget to close a tag)

Dependencies
-------------
* lxml - may be possible to replace this with python's inbuilt etree support

Installation
-------------

::

    $ virtualenv env
    $ . env/bin/activate
    # pip install wither

Compatibility
--------------
Wither supports Python 2.7 and Python 3.2 and up as its supported python 
versions but may also work on earlier versions of python 3 and python 2.6. 
while these platforms are automatically tested to check for breakages these 
earlier versions are not officially supported and failing tests are for 
informational purposes only.

Motivations
------------
Wither is very much a project that was written 'because i can'. I have multiple 
python modules that abuse python syntax in interesting ways to do things like 
pattern matching of automatic retry of transactions for Databases that are all 
concise and visually appealing.

after seeing the 'with' statement and its use in python 2.6 with nesting for 
using multiple context generators (instead of python 2.7's flattened version) i 
decided to see if i could use this to upgrade an existing XML generation 
program that used a similar concept with object.

the aim of this project is not to create a fast generator but create something 
that looks 'right' when included inline with python code and support dynamic 
features like a string template library would.

Further Ideas
-------------
By using 'yield' in strategic spots it may be possible to partially render a 
template allowing one to send a prerendered 'frame' (or the head part of it at 
least) and then generate the body followed by the tail (of the frame) to the 
client thereby speeding up transmission of the first byte to the client and 
avoiding a dogpile of transmission at the end of the request. this should allow 
clients to render their pages quicker as well as they have partial data with 
which they can start planning out the layout of the page

