20 lines
654 B
Python
20 lines
654 B
Python
class Singleton(type):
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"""
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Singleton Metaclass.
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Enforces any object using this metaclass to only create a single instance.
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- External Usage documentation: U{https://github.com/tylerlaberge/PyPatterns/wiki/Creational-Pattern-Usage}
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- External Singleton Pattern documentation: U{https://en.wikipedia.org/wiki/Singleton_pattern}
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"""
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__instance = None
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def __call__(cls, *args, **kwargs):
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"""
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Override the __call__ method to make sure only one instance is created.
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"""
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if cls.__instance is None:
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cls.__instance = type.__call__(cls, *args, **kwargs)
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return cls.__instance
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