Unlike the ordinary Element factory, the E factory allows you to pass in more than just a tag and some optional attributes; you can also pass in text and other elements. The text is added as either text or tail attributes, and elements are inserted at the right spot. Some small examples::
>>> from lxml import etree as ET >>> from lxml.builder import E
Here's a somewhat larger example; this shows how to generate HTML documents, using a mix of prepared factory functions for inline elements, nested ``E.tag`` calls, and embedded XHTML fragments::
# some common inline elements A = E.a I = E.i B = E.b
def CLASS(v): # helper function, 'class' is a reserved word return {'class': v}
page = ( E.html( E.head( E.title("This is a sample document") ), E.body( E.h1("Hello!", CLASS("title")), E.p("This is a paragraph with ", B("bold"), " text in it!"), E.p("This is another paragraph, with a ", A("link", href="http://www.python.org"), "."), E.p("Here are some reserved characters: <spam&egg>."), ET.XML("<p>And finally, here is an embedded XHTML fragment.</p>"), ) ) )
print ET.tostring(page)
Here's a prettyprinted version of the output from the above script::
<html> <head> <title>This is a sample document</title> </head> <body> <h1 class="title">Hello!</h1> <p>This is a paragraph with <b>bold</b> text in it!</p> <p>This is another paragraph, with <a href="http://www.python.org">link</a>.</p> <p>Here are some reserved characters: <spam&egg>.</p> <p>And finally, here is an embedded XHTML fragment.</p> </body> </html>
For namespace support, you can pass a namespace map (``nsmap``) and/or a specific target ``namespace`` to the ElementMaker class::
>>> E = ElementMaker(namespace="http://my.ns/") >>> print(ET.tostring( E.test )) <test xmlns="http://my.ns/"/>