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			109 lines
		
	
	
	
		
			3.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			109 lines
		
	
	
	
		
			3.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """Python version compatibility support for minidom.
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| 
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| This module contains internal implementation details and
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| should not be imported; use xml.dom.minidom instead.
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| """
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| 
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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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| 
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| __all__ = ["NodeList", "EmptyNodeList", "StringTypes", "defproperty"]
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| 
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| import xml.dom
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| 
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| StringTypes = (str,)
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| 
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| 
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| class NodeList(list):
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|     __slots__ = ()
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| 
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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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| 
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|     def _get_length(self):
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|         return len(self)
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| 
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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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| 
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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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| 
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|     # For backward compatibility
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|     def __setstate__(self, state):
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|         if state is None:
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|             state = []
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|         self[:] = state
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| 
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| 
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| class EmptyNodeList(tuple):
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|     __slots__ = ()
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| 
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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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| 
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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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| 
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|     def item(self, index):
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|         return None
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| 
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|     def _get_length(self):
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|         return 0
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| 
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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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| 
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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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| 
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| 
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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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