Package lxml :: Module builder :: Class ElementMaker
[hide private]
[frames] | no frames]

Class ElementMaker

source code

object --+

Element generator factory.

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

    >>> from lxml import etree as ET
    >>> from lxml.builder import E

    >>> ET.tostring(E("tag"))
    >>> ET.tostring(E("tag", "text"))
    >>> ET.tostring(E("tag", "text", key="value"))
    '<tag key="value">text</tag>'
    >>> ET.tostring(E("tag", E("subtag", "text"), "tail"))

For simple tags, the factory also allows you to write ``E.tag(...)`` instead
of ``E('tag', ...)``::

    >>> ET.tostring(E.tag())
    >>> ET.tostring(E.tag("text"))
    >>> ET.tostring(E.tag(E.subtag("text"), "tail"))

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.title("This is a sample document")
                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=""), "."),
                E.p("Here are some reservered 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::

        <title>This is a sample document</title>
        <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="">link</a>.</p>
        <p>Here are some reservered characters: &lt;spam&amp;egg&gt;.</p>
        <p>And finally, here is an embedded XHTML fragment.</p>

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/"/>

>>> E = ElementMaker(namespace="http://my.ns/", nsmap={'p':'http://my.ns/'})
>>> print(ET.tostring( E.test ))
<p:test xmlns:p="http://my.ns/"/>

Instance Methods [hide private]
__init__(self, typemap=None, namespace=None, nsmap=None, makeelement=None)
x.__init__(...) initializes x; see x.__class__.__doc__ for signature
source code
__call__(self, tag, *children, **attrib) source code
__getattr__(self, tag) source code

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Properties [hide private]

Inherited from object: __class__

Method Details [hide private]

__init__(self, typemap=None, namespace=None, nsmap=None, makeelement=None)

source code 
x.__init__(...) initializes x; see x.__class__.__doc__ for signature
Overrides: object.__init__
(inherited documentation)