40 lines
738 B
Python
40 lines
738 B
Python
"""
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Testing ``KeyIsValueDict``::
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>>> adict = KeyIsValueDict()
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>>> len(adict)
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0
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>>> adict['first']
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'first'
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>>> adict
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{'first': 'first'}
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>>> adict['second']
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'second'
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>>> len(adict)
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2
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>>> adict
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{'first': 'first', 'second': 'second'}
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>>> adict['__magic__']
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Traceback (most recent call last):
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...
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KeyError: '__magic__'
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"""
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class KeyIsValueDict(dict):
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def __missing__(self, key):
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if key.startswith('__') and key.endswith('__'):
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raise KeyError(key)
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self[key] = key
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return key
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class NanoEnumMeta(type):
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def __prepare__(name, bases, **kwargs):
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return KeyIsValueDict()
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class NanoEnum(metaclass=NanoEnumMeta):
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pass
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