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			105 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
"""Python version compatibility support for minidom."""
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# This module should only be imported using "import *".
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#
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# The following names are defined:
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#
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#   NodeList      -- lightest possible NodeList implementation
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#
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#   EmptyNodeList -- lightest possible NodeList that is guaranteed to
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#                    remain empty (immutable)
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#
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#   StringTypes   -- tuple of defined string types
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#
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#   defproperty   -- function used in conjunction with GetattrMagic;
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#                    using these together is needed to make them work
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#                    as efficiently as possible in both Python 2.2+
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#                    and older versions.  For example:
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#
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#                        class MyClass(GetattrMagic):
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#                            def _get_myattr(self):
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#                                return something
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#
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#                        defproperty(MyClass, "myattr",
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#                                    "return some value")
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#
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#                    For Python 2.2 and newer, this will construct a
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#                    property object on the class, which avoids
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#                    needing to override __getattr__().  It will only
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#                    work for read-only attributes.
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#
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#                    For older versions of Python, inheriting from
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#                    GetattrMagic will use the traditional
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#                    __getattr__() hackery to achieve the same effect,
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#                    but less efficiently.
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#
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#                    defproperty() should be used for each version of
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#                    the relevant _get_<property>() function.
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__all__ = ["NodeList", "EmptyNodeList", "StringTypes", "defproperty"]
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import xml.dom
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StringTypes = (str,)
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class NodeList(list):
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    __slots__ = ()
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    def item(self, index):
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        if 0 <= index < len(self):
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            return self[index]
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    def _get_length(self):
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        return len(self)
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    def _set_length(self, value):
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        raise xml.dom.NoModificationAllowedErr(
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            "attempt to modify read-only attribute 'length'")
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    length = property(_get_length, _set_length,
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                      doc="The number of nodes in the NodeList.")
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    def __getstate__(self):
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        return list(self)
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    def __setstate__(self, state):
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        self[:] = state
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class EmptyNodeList(tuple):
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    __slots__ = ()
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    def __add__(self, other):
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        NL = NodeList()
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        NL.extend(other)
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        return NL
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    def __radd__(self, other):
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        NL = NodeList()
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        NL.extend(other)
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        return NL
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    def item(self, index):
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        return None
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    def _get_length(self):
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        return 0
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    def _set_length(self, value):
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        raise xml.dom.NoModificationAllowedErr(
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            "attempt to modify read-only attribute 'length'")
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    length = property(_get_length, _set_length,
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                      doc="The number of nodes in the NodeList.")
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def defproperty(klass, name, doc):
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    get = getattr(klass, ("_get_" + name))
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    def set(self, value, name=name):
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        raise xml.dom.NoModificationAllowedErr(
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            "attempt to modify read-only attribute " + repr(name))
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    assert not hasattr(klass, "_set_" + name), \
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           "expected not to find _set_" + name
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    prop = property(get, set, doc=doc)
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    setattr(klass, name, prop)
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