lxml.builder.ElementMaker

Package lxml :: Module builder :: Class ElementMaker |
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# Class ElementMaker

source code

    object --+
             |
            ElementMaker

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 examples:

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

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

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

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

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 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:

    <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 reservered characters: &lt;spam&amp;egg&gt;.</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/"/>

    >>> 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 help(type(x)) 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) (Constructor) | source code
x.__init__(...) initializes x; see help(type(x)) for signature Overrides: object.__init__ (inherited documentation)