54 lines
1.1 KiB
Plaintext
54 lines
1.1 KiB
Plaintext
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Wrapping
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=========
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a wrapper can restrict, heritage cannot.
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::
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# ____________________________________________________________
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# Base objects
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class Element:
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def __init__(self, name):
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self.name = name
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def __repr__(self):
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return "<Element %s>"% self.name
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# ____________________________________________________________
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# Wrapped objects
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class W_Element:
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def __init__(self, name, wrap):
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self._name = "wrapped_element" or name
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self._w = wrap
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def __getattr__(self, name):
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return getattr(self._w, name)
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def get_w(self, name):
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return getattr(self._w, name)
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def set_w(self, name, value):
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return setattr(self._w, name, value)
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_w = property (get_w, set_w)
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def __repr__(self):
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return "[W_Element %s]"% repr(self._name)
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# ____________________________________________________________
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# tests
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e = Element('element 1')
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w_e = W_Element('w_element 1', e)
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e.a = 2
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print w_e.a
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print w_e
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w_e.b = 5
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print w_e.b
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