Module xhtml

Bases:: _HTMLActionTag

<a> tags

Methods:: _async_action(self, renderer, action, with_request, permissions, subject): Register an asynchronous action; sync_action(self, renderer, action, with_request, permissions, subject): Register a synchronous action

Attributes:: _actions = (41, None, 'onclick'); async_action = _async_action

Method xhtml.A._async_action

Back to xhtml.A

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Method xhtml.A.sync_action

Back to xhtml.A

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Class xhtml.AsyncHeadRenderer

Bases:: HeadRenderer

Methods:: __init__(self, static_url): Renderer initialisation; _css(self, style): Memorize an in-line anonymous css style; _get_anonymous_css(self): Return the list of the in-line anonymous css styles, sorted by order of insertion; _get_anonymous_javascript(self): Return the list of anonymous javascript codes, sorted by order of insertion; _javascript(self, script): Memorize an in-line anonymous javascript code; _script(self, append, tag, script):; _style(self, append, tag, style):

Method xhtml.AsyncHeadRenderer.init

Arguments:: self, static_url

Renderer initialisation

The HeadRenderer keeps track of the javascript and css used by every views, to be able to concatenate them into the <head> section.

Method xhtml.AsyncHeadRenderer._css

Arguments:: self, style

Memorize an in-line anonymous css style

In:

style -- the css style

Method xhtml.AsyncHeadRenderer._get_anonymous_css

Arguments:: self

Return the list of the in-line anonymous css styles, sorted by order of insertion

Return:

list of css styles

Method xhtml.AsyncHeadRenderer._get_anonymous_javascript

Arguments:: self

Return the list of anonymous javascript codes, sorted by order of insertion

Return:

list of javascript codes

Method xhtml.AsyncHeadRenderer._javascript

Arguments:: self, script

Memorize an in-line anonymous javascript code

In:

script -- the javascript code

Class xhtml.AsyncRenderer

Bases:: Renderer

The XHTML asynchronous renderer

Methods:: AsyncRenderer(self, *args, **kw): Create an associated asynchronous HTML renderer; SyncRenderer(self, *args, **kw): Create an associated synchronous HTML renderer; __init__(self, parent=None, session=None, request=None, response=None, callbacks=None, static_url='', static_path='', url='/', async_header=False): Renderer initialisation; _css(self, style):; _javascript(self, js):; action(self, tag, action, with_request, permissions, subject): Register an asynchronous action on a tag; end_rendering(self, output): Method called after a component is rendered; get_async_root(self):; javascript_url(self, url):; start_rendering(self, component, model):

Attributes:: head_renderer_factory = AsyncHeadRenderer

Method xhtml.AsyncRenderer.AsyncRenderer

Arguments:: self, *args, **kw

Create an associated asynchronous HTML renderer

Return:

a new asynchronous renderer

Method xhtml.AsyncRenderer.SyncRenderer

Arguments:: self, *args, **kw

Create an associated synchronous HTML renderer

Return:

a new synchronous renderer

Method xhtml.AsyncRenderer.init

Arguments:: self, parent=None, session=None, request=None, response=None, callbacks=None, static_url='', static_path='', url='/', async_header=False

Renderer initialisation

In:

parent -- parent renderer
session -- the session object
request -- the request object
response -- the response object
callbacks -- the registered actions on the tags
static_url -- url of the static contents of the application
static_path -- path of the static contents of the application
url -- url prefix of the application
async_header -- is the head renderer to create a synchronous or an asynchronous one?

Method xhtml.AsyncRenderer.action

Arguments:: self, tag, action, with_request, permissions, subject

In:

tag -- the tag
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Method xhtml.AsyncRenderer.end_rendering

Arguments:: self, output

Method called after a component is rendered

In:

output -- rendered tree

Out:

rendered tree

Class xhtml.CheckboxInput

Back to xhtml.CheckboxInput

Bases:: _HTMLActionTag

<input> tags with type=checkbox attributes

Methods:: selected(self, flag): (de)Select the tag

Attributes:: _actions = (1, 'name', 'onclick')

Method xhtml.CheckboxInput.selected

Arguments:: self, flag

(de)Select the tag

In:

flag -- boolean to deselect / select the tag

Return:

self

Class xhtml.FileInput

Bases:: _HTMLActionTag

<input> tags with type=file attributes

Methods:: init(self, renderer): Initialisation

Attributes:: _actions = (1, 'name', 'onchange')

Method xhtml.FileInput.init

Back to xhtml.FileInput

Arguments:: self, renderer

Initialisation

In:

renderer -- the current renderer

Return:

self

Class xhtml.Form

Bases:: xhtml_base._HTMLTag

The <form> tag

Methods:: add_child(self, child): Add a child to this <form> tag; init(self, renderer): Initialisation; post_action(self, action, with_request=False, permissions=None, subject=None): Register an action that will be executed after the actions of the form elements; pre_action(self, action, with_request=False, permissions=None, subject=None): Register an action that will be executed before the actions of the form elements

Method xhtml.Form.add_child

Arguments:: self, child

Add a child to this <form> tag

Delete the existing <form> tags in the child tree

Method xhtml.Form.init

Arguments:: self, renderer

Initialisation

In:

renderer -- the current renderer

Return:

self

Method xhtml.Form.post_action

Arguments:: self, action, with_request=False, permissions=None, subject=None

In:

action -- action
with_request -- will the request and response object be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Return:

self

Method xhtml.Form.pre_action

Arguments:: self, action, with_request=False, permissions=None, subject=None

In:

action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Return:

self

Class xhtml.HeadRenderer

Bases:: xhtml_base.HeadRenderer

The XHTML head Renderer

This renderer knows about the static contents of the application

Methods:: __init__(self, static_url): Renderer initialisation; _get_css_url(self): Return the list of css URLs, sorted by order of insertion; _get_javascript_url(self): Return the list of javascript URLs, sorted by order of insertion; _get_named_css(self): Return the list of the in-line named css styles, sorted by order of insertion; _get_named_javascript(self): Return the list of named javascript codes, sorted by order of insertion; _script(self, append, tag, script):; _style(self, append, tag, style):; css(self, name, style, **kw): Memorize an in-line named css style; css_url(self, url, **kw): Memorize a css style URL; javascript(self, name, script, **kw): Memorize an in-line named javascript code; javascript_url(self, url, **kw): Memorize a javascript URL

Method xhtml.HeadRenderer.init

Arguments:: self, static_url

Renderer initialisation

The HeadRenderer keeps track of the javascript and css used by every views, to be able to concatenate them into the <head> section.

Method xhtml.HeadRenderer._get_css_url

Arguments:: self

Return the list of css URLs, sorted by order of insertion

Return:

list of css (URLs, attributes)

Method xhtml.HeadRenderer._get_javascript_url

Arguments:: self

Return the list of javascript URLs, sorted by order of insertion

Return:

list of javascript (URLs, attributes)

Method xhtml.HeadRenderer._get_named_css

Arguments:: self

Return the list of the in-line named css styles, sorted by order of insertion

Return:

list of (name, css style, attributes)

Method xhtml.HeadRenderer._get_named_javascript

Arguments:: self

Return the list of named javascript codes, sorted by order of insertion

Return:

list of (name, javascript code, attributes)

Method xhtml.HeadRenderer.css

Arguments:: self, name, style, **kw

Memorize an in-line named css style

In:

name -- unique name of this css style (to prevent double definition)
style -- the css style
kw -- attributes of the generated <style> tag

Return:

()

Method xhtml.HeadRenderer.css_url

Arguments:: self, url, **kw

Memorize a css style URL

In:

url -- the css style URL
kw -- attributes of the generated <link> tag

Return:

()

Method xhtml.HeadRenderer.javascript

Arguments:: self, name, script, **kw

Memorize an in-line named javascript code

In:

name -- unique name of this javascript code (to prevent double definition)
script -- the javascript code
kw -- attributes of the generated <script> tag

Return:

()

Method xhtml.HeadRenderer.javascript_url

Arguments:: self, url, **kw

Memorize a javascript URL

In:

url -- the javascript URL
kw -- attributes of the the generated <script> tag

Return:

()

Class xhtml.HiddenInput

Bases:: _HTMLActionTag

<input> tags with type=hidden attributes

Attributes:: _actions = (1, 'name', 'onchange')

Class xhtml.ImageInput

Bases:: _HTMLActionTag

<input> tags with type=image attributes

Methods:: add_child(self, child): Add attributes to the image input; async_action(self, renderer, action, with_request, permissions, subject): Register an asynchronous action

Attributes:: _actions = (5, 'name', 'onclick')

Method xhtml.ImageInput.add_child

Back to xhtml.ImageInput

Arguments:: self, child

Add attributes to the image input

In:

child -- attributes dictionary

Method xhtml.ImageInput.async_action

Back to xhtml.ImageInput

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Class xhtml.Img

Bases:: _HTMLActionTag

<img> tags

Methods:: _set_content_type(self, request, action, with_request): Generate the image and guess its format; add_child(self, child): Add attributes to the image; sync_action(self, renderer, action, with_request, permissions, subject): Register a synchronous action

Attributes:: async_action = sync_action

Method xhtml.Img._set_content_type

Back to xhtml.Img

Arguments:: self, request, action, with_request

Generate the image and guess its format

In:

request -- the web request object
action -- function to call to generate the image data
with_request -- will the request and response objects be passed to the action ?

Return:

new response object raised

Method xhtml.Img.add_child

Back to xhtml.Img

Arguments:: self, child

Add attributes to the image

In:

child -- attributes dictionary

Method xhtml.Img.sync_action

Back to xhtml.Img

Arguments:: self, renderer, action, with_request, permissions, subject

The action will have to return the image data

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Class xhtml.Label

Bases:: xhtml_base._HTMLTag

<label> tags

Methods:: init(self, renderer): Initialisation

Method xhtml.Label.init

Back to xhtml.Label

Arguments:: self, renderer

Initialisation

In:

renderer -- the current renderer

Return:

self

Class xhtml.Option

Bases:: xhtml_base._HTMLTag

<options> tags

Methods:: selected(self, values): (de)Select the tags

Method xhtml.Option.selected

Back to xhtml.Option

Arguments:: self, values

(de)Select the tags

In:

values -- name or list of names of the tags to select

Return:

self

Class xhtml.PasswordInput

Bases:: _HTMLActionTag

<input> tags with type=password attributes

Attributes:: _actions = (1, 'name', 'onchange')

Class xhtml.RadioInput

Bases:: _HTMLActionTag

<input> tags with type=radio attributes

Methods:: selected(self, flag): (de)Select the tag

Attributes:: _actions = (2, 'value', 'onclick')

Method xhtml.RadioInput.selected

Back to xhtml.RadioInput

Arguments:: self, flag

(de)Select the tag

In:

flag -- boolean to deselect / select the tag

Return:

self

Class xhtml.Renderer

Bases:: xhtml_base.Renderer

The XHTML synchronous renderer

Methods:: AsyncRenderer(self, *args, **kw): Create an associated asynchronous HTML renderer; SyncRenderer(self, *args, **kw): Create an associated synchronous HTML renderer; __init__(self, parent=None, session=None, request=None, response=None, callbacks=None, static_url='', static_path='', url='/'): Renderer initialisation; action(self, tag, action, with_request, permissions, subject): Register a synchronous action on a tag; add_sessionid_in_form(self, form): Add the session and continuation ids into a <form>; add_sessionid_in_url(self, u='', params=None, sep='&'): Add the session and continuation ids into an url; class_init(cls, specialTags): Class initialisation; content_type(self): Generate the content type of the document; decorate_error(self, element, error): During the rendering, highlight an element that has an error; doctype(self): Generate the DOCTYPE of the document; makeelement(self, tag): Make a tag; parse_html(self, source, fragment=False, no_leading_text=False, xhtml=False, **kw): Parse a (X)HTML file; parse_xml(self, source, fragment=False, no_leading_text=False, **kw): Parse a XML file; register_callback(self, priority, f, with_request, render=None): Register an action; start_rendering(self, component, model): Method called before to render a component

Attributes:: HTML_DOCTYPE = '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">'; XML_DOCTYPE = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">'; _specialTags = dict(text_input = TextInput, radio_input = RadioInput, checkbox_input = CheckboxInput, submit_input = SubmitInput, hidden_input = HiddenInput, file_input = FileInput, password_input = PasswordInput, image_input = ImageInput); a = TagProp('a', set(xhtml_base.allattrs + xhtml_base.focusattrs + ('charset', 'type', 'name', 'href', 'hreflang', 'rel', 'rev', 'shape', 'coords', 'target', 'oncontextmenu')), A); area = TagProp('area', set(xhtml_base.allattrs + xhtml_base.focusattrs + ('shape', 'coords', 'href', 'nohref', 'alt', 'target')), A); button = TagProp('button', set(xhtml_base.allattrs + xhtml_base.focusattrs + ('name', 'value', 'type', 'disabled')), SubmitInput); form = TagProp('form', set(xhtml_base.allattrs + ('action', 'method', 'name', 'enctype', 'onsubmit', 'onreset', 'accept_charset', 'target')), Form); head_renderer_factory = HeadRenderer; img = TagProp('img', set(xhtml_base.allattrs + ('src', 'alt', 'name', 'longdesc', 'width', 'height', 'usemap', 'ismapalign', 'border', 'hspace', 'vspace', 'lowsrc')), Img); input = TagProp('input', set(xhtml_base.allattrs + xhtml_base.focusattrs + ('type', 'name', 'value', 'checked', 'disabled', 'readonly', 'size', 'maxlength', 'srcalt', 'usemap', 'onselect', 'onchange', 'accept', 'align', 'border')), TextInput); label = TagProp('label', set(xhtml_base.allattrs + ('for', 'accesskey', 'onfocus', 'onblur')), Label); option = TagProp('option', set(xhtml_base.allattrs + ('selected', 'disabled', 'label', 'value')), Option); script = TagProp('script', set(('id', 'charset', 'type', 'language', 'src', 'defer')), Script); select = TagProp('select', set(xhtml_base.allattrs + ('name', 'size', 'multiple', 'disabled', 'tabindex', 'onfocus', 'onblur', 'onchange', 'rows')), Select); style = TagProp('style', set(xhtml_base.i18nattrs + ('id', 'type', 'media', 'title')), Style); textarea = TagProp('textarea', set(xhtml_base.allattrs + xhtml_base.focusattrs + ('name', 'rows', 'cols', 'disabled', 'readonly', 'onselect', 'onchange', 'wrap')), TextArea)

Method xhtml.Renderer.AsyncRenderer

Arguments:: self, *args, **kw

Create an associated asynchronous HTML renderer

Return:

a new asynchronous renderer

Method xhtml.Renderer.SyncRenderer

Arguments:: self, *args, **kw

Create an associated synchronous HTML renderer

Return:

a new synchronous renderer

Method xhtml.Renderer.init

Arguments:: self, parent=None, session=None, request=None, response=None, callbacks=None, static_url='', static_path='', url='/'

Renderer initialisation

In:

parent -- parent renderer
session -- the session object
request -- the request object
response -- the response object
callbacks -- the registered actions on the tags
static_url -- url of the static contents of the application
static_path -- path of the static contents of the application
url -- url prefix of the application

Method xhtml.Renderer.action

Arguments:: self, tag, action, with_request, permissions, subject

In:

tag -- the tag
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Method xhtml.Renderer.add_sessionid_in_form

Arguments:: self, form

Add the session and continuation ids into a <form>

Forward this call to the sessions manager

In:

form -- the form tag

Method xhtml.Renderer.add_sessionid_in_url

Arguments:: self, u='', params=None, sep='&'

Add the session and continuation ids into an url

Forward this call to the sessions manager

In:

u -- the url
params -- query string of the url

Return:

the completed url

Method xhtml.Renderer.class_init

Back to xhtml.Renderer.class_init

Arguments:: cls, specialTags

Class initialisation

In:: -- special_tags -- tags that have a special factory

Decorators:: @classmethod

Classes:: CustomLookup(ET.CustomElementClassLookup):

Class xhtml.Renderer.class_init.CustomLookup

Bases:: ET.CustomElementClassLookup

Methods:: __init__(self, specialTags, defaultLookup):; lookup(self, node_type, document, namespace, name):

Method xhtml.Renderer.content_type

Arguments:: self

Generate the content type of the document

If a content type was set on the response object, use it Else, use the HTML ou XHTML content type of this renderer

Return:

the content type

Decorators:: @property

Method xhtml.Renderer.decorate_error

Arguments:: self, element, error

During the rendering, highlight an element that has an error

In:

element -- the element in error
error -- the error text

Method xhtml.Renderer.doctype

Arguments:: self

Generate the DOCTYPE of the document

If a doctype was set on the response object, use it Else, use the HTML ou XHTML doctypes of this renderer

Return:

the doctype

Decorators:: @property

Method xhtml.Renderer.makeelement

Arguments:: self, tag

Make a tag

In:

tag -- name of the tag to create

Return:

the new tag

Method xhtml.Renderer.parse_html

Arguments:: self, source, fragment=False, no_leading_text=False, xhtml=False, **kw

Parse a (X)HTML file

In:

source -- can be a filename or a file object
fragment -- if True, can parse a HTML fragment i.e a HTML without a unique root
no_leading_text -- if fragment is True, no_leading_text is False and the HTML to parsed begins by a text, this text is keeped
xhtml -- is the HTML to parse a valid XHTML ?
kw -- keywords parameters are passed to the HTML parser

Return:

the root element of the parsed HTML, if fragment is False
a list of HTML elements, if fragment is True

Method xhtml.Renderer.parse_xml

Arguments:: self, source, fragment=False, no_leading_text=False, **kw

Parse a XML file

In:

source -- can be a filename or a file object
fragment -- if True, can parse a XML fragment i.e a XML without a unique root
no_leading_text -- if fragment is True, no_leading_text is False and the XML to parsed begins by a text, this text is keeped
kw -- keywords parameters are passed to the XML parser

Return:

the root element of the parsed XML, if fragment is False
a list of XML elements, if fragment is True

Method xhtml.Renderer.register_callback

Arguments:: self, priority, f, with_request, render=None

Forward the call to the callbacks object

In:

priority - -priority of the action
f -- the action
with_request -- will the request and response objects be passed to the action ?
render -- render method to generate the view after the f action will be called

Method xhtml.Renderer.start_rendering

Arguments:: self, component, model

Method called before to render a component

In:

component -- component to render
model -- name of the view to use

Class xhtml.Select

Bases:: _HTMLActionTag

<select> tags

Methods:: action(self, action, with_request=False, permissions=None, subject=None): Register an action

Attributes:: _actions = (1, 'name', 'onchange')

Method xhtml.Select.action

Back to xhtml.Select

Arguments:: self, action, with_request=False, permissions=None, subject=None

In:

action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Return:

self

Class xhtml.SubmitInput

Back to xhtml.SubmitInput

Bases:: _HTMLActionTag

<input> tags with type=submit attributes

Methods:: async_action(self, renderer, action, with_request, permissions, subject): Register an asynchronous action

Attributes:: _actions = (4, 'name', 'onclick')

Method xhtml.SubmitInput.async_action

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Class xhtml.TextArea

Bases:: _HTMLActionTag

<textarea> tags

Methods:: action(self, action, with_request=False, permissions=None, subject=None): Register an action

Attributes:: _actions = (1, 'name', 'onchange')

Method xhtml.TextArea.action

Back to xhtml.TextArea

Arguments:: self, action, with_request=False, permissions=None, subject=None

In:

action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Return:

self

Class xhtml.TextInput

Bases:: _HTMLActionTag

Dispatcher class for all the <input> tags

Methods:: __call__(self, *children, **attrib):

Attributes:: _actions = (1, 'name', 'onchange')

Class xhtml._HTMLActionTag

Back to xhtml._HTMLActionTag

Bases:: xhtml_base._HTMLTag

Base class of all the tags with a .action() method

Methods:: _async_action(self, renderer, action, with_request, permissions, subject): Register an asynchronous action; action(self, action, with_request=False, permissions=None, subject=None): Register an action; sync_action(self, renderer, action, with_request, permissions, subject): Register a synchronous action

Attributes:: async_action = sync_action

Method xhtml._HTMLActionTag._async_action

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Method xhtml._HTMLActionTag.action

Back to xhtml._HTMLActionTag

Arguments:: self, action, with_request=False, permissions=None, subject=None

In:

action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Return:

self

Method xhtml._HTMLActionTag.sync_action

Back to xhtml._HTMLActionTag

Arguments:: self, renderer, action, with_request, permissions, subject

In:

renderer -- the current renderer
action -- action
with_request -- will the request and response objects be passed to the action ?
permissions -- permissions needed to execute the action
subject -- subject to test the permissions on

Method xhtml.absolute_url

Arguments:: url, static

Convert a relative URL of a static content to an absolute one

In:

url -- url to convert
static -- URL prefix of the static contents

Return:

an absolute URL

Method xhtml.add_attribute

Arguments:: self, name, value

Add an attribute with a ajax.Update value

In:

self -- the tag
name -- name of the attribute
value -- ajax.Update value

Decorators:: @peak.rules.when(xml.add_attribute, (xml._Tag, basestring, ajax.Update))

Method xhtml.add_attribute

Arguments:: self, name, value

Add an attribute with a function value

In:

self -- the tag
name -- name of the attribute
value -- function value

Decorators:: @peak.rules.when(xml.add_attribute, (xml._Tag, basestring, types.FunctionType))

Method xhtml.add_attribute

Arguments:: self, name, value

Add an attribute with a method value

In:

self -- the tag
name -- name of the attribute
value -- method value

Decorators:: @peak.rules.when(xml.add_attribute, (xml._Tag, basestring, types.MethodType))

Method xhtml.add_attribute

Arguments:: self, name, value

Add an attribute with a ajax.JS value

In:

self -- the tag
name -- name of the attribute
value -- ajax.JS value

Decorators:: @peak.rules.when(xml.add_attribute, (xml._Tag, basestring, ajax.JS))

Method xhtml.add_child

Arguments:: next_method, self, script

Add a <script> to a tag

In:

self -- the tag
script -- the script to add

Decorators:: @peak.rules.when(xml.add_child, (xhtml_base._HTMLTag, Script))

Method xhtml.add_child

Arguments:: next_method, self, style

Add a <style> to a tag

In:

self -- the tag
style -- the style to add

Decorators:: @peak.rules.when(xml.add_child, (xhtml_base._HTMLTag, Style))

Method xhtml.render

Arguments:: self, h, *args

Generate the <head> tree

In:

h -- not used

Return:

the <head> tree

Decorators:: @presentation.render_for(HeadRenderer)

Method xhtml.render