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W[;  ã                   @   s‚   d dl mZmZ d dlmZ d dlmZ d dlmZm	Z	 d dlm
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 G dd„ deƒZejZedd	„ ƒZeeƒG d
d„ deƒƒZdS )é    )ÚdivisionÚabsolute_import)Úimplementer)ÚIRenderable)ÚMissingRenderMethodÚUnexposedMethodError)ÚMissingTemplateLoaderc                   @   s@   e Zd ZdZddd„Zdd„ Zeƒ Zefdd„Ze	d	d
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dS )ÚExposea‡  
    Helper for exposing methods for various uses using a simple decorator-style
    callable.

    Instances of this class can be called with one or more functions as
    positional arguments.  The names of these functions will be added to a list
    on the class object of which they are methods.

    @ivar attributeName: The attribute with which exposed methods will be
    tracked.
    Nc                 C   s
   || _ d S ©N)Údoc)Úselfr   © r   ú6/usr/lib/python3/dist-packages/twisted/web/_element.pyÚ__init__   s    zExpose.__init__c                 G   s8   |st dƒ‚|D ]}t|dg ƒ|_|j | ¡ q|d S )aH  
        Add one or more functions to the set of exposed functions.

        This is a way to declare something about a class definition, similar to
        L{zope.interface.declarations.implementer}.  Use it like this::

            magic = Expose('perform extra magic')
            class Foo(Bar):
                def twiddle(self, x, y):
                    ...
                def frob(self, a, b):
                    ...
                magic(twiddle, frob)

        Later you can query the object::

            aFoo = Foo()
            magic.get(aFoo, 'twiddle')(x=1, y=2)

        The call to C{get} will fail if the name it is given has not been
        exposed using C{magic}.

        @param funcObjs: One or more function objects which will be exposed to
        the client.

        @return: The first of C{funcObjs}.
        z,expose() takes at least 1 argument (0 given)ÚexposedThroughr   )Ú	TypeErrorÚgetattrr   Úappend)r   ZfuncObjsZfObjr   r   r   Ú__call__   s    zExpose.__call__c                 C   s<   t ||dƒ}t |dg ƒ}| |kr8|| jkr4t| |ƒ‚|S |S )aB  
        Retrieve an exposed method with the given name from the given instance.

        @raise UnexposedMethodError: Raised if C{default} is not specified and
        there is no exposed method with the given name.

        @return: A callable object for the named method assigned to the given
        instance.
        Nr   )r   Ú
_nodefaultr   )r   ÚinstanceZ
methodNameÚdefaultÚmethodr   r   r   r   ÚgetC   s    


z
Expose.getc                 C   s
   | |j ƒS )a  
        Slight hack to make users of this class appear to have a docstring to
        documentation generators, by defining them with a decorator.  (This hack
        should be removed when epydoc can be convinced to use some other method
        for documenting.)
        )Ú__doc__)ÚclsZthunkr   r   r   Ú_withDocumentationV   s    zExpose._withDocumentation)N)Ú__name__Ú
__module__Ú__qualname__r   r   r   Úobjectr   r   Úclassmethodr   r   r   r   r   r	      s   
$r	   c                   C   s   dS )aâ  
    Decorate with L{renderer} to use methods as template render directives.

    For example::

        class Foo(Element):
            @renderer
            def twiddle(self, request, tag):
                return tag('Hello, world.')

        <div xmlns:t="http://twistedmatrix.com/ns/twisted.web.template/0.1">
            <span t:render="twiddle" />
        </div>

    Will result in this final output::

        <div>
            <span>Hello, world.</span>
        </div>
    Nr   r   r   r   r   Úrenderere   s    r"   c                   @   s.   e Zd ZdZdZd	dd„Zdd„ Zdd„ ZdS )
ÚElementaØ  
    Base for classes which can render part of a page.

    An Element is a renderer that can be embedded in a stan document and can
    hook its template (from the loader) up to render methods.

    An Element might be used to encapsulate the rendering of a complex piece of
    data which is to be displayed in multiple different contexts.  The Element
    allows the rendering logic to be easily re-used in different ways.

    Element returns render methods which are registered using
    L{twisted.web._element.renderer}.  For example::

        class Menu(Element):
            @renderer
            def items(self, request, tag):
                ....

    Render methods are invoked with two arguments: first, the
    L{twisted.web.http.Request} being served and second, the tag object which
    "invoked" the render method.

    @type loader: L{ITemplateLoader} provider
    @ivar loader: The factory which will be used to load documents to
        return from C{render}.
    Nc                 C   s   |d k	r|| _ d S r
   )Úloader)r   r$   r   r   r   r   œ   s    zElement.__init__c                 C   s$   t  | |d¡}|dkr t| |ƒ‚|S )z=
        Look up and return the named render method.
        N)r"   r   r   )r   Únamer   r   r   r   ÚlookupRenderMethod¡   s    
zElement.lookupRenderMethodc                 C   s   | j }|dkrt| ƒ‚| ¡ S )aê  
        Implement L{IRenderable} to allow one L{Element} to be embedded in
        another's template or rendering output.

        (This will simply load the template from the C{loader}; when used in a
        template, the flattening engine will keep track of this object
        separately as the object to lookup renderers on and call
        L{Element.renderer} to look them up.  The resulting object from this
        method is not directly associated with this L{Element}.)
        N)r$   r   Úload)r   Zrequestr$   r   r   r   Úrender«   s    zElement.render)N)r   r   r   r   r$   r   r&   r(   r   r   r   r   r#   ~   s
   

r#   N)Z
__future__r   r   Zzope.interfacer   Ztwisted.web.iwebr   Ztwisted.web.errorr   r   r   r    r	   r   Zexposerr"   r#   r   r   r   r   Ú<module>   s   U
