19 lines
824 B
Python
19 lines
824 B
Python
# Metaclass for mixing slots and descriptors
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# From "Programming in Python 3" by Mark Summerfield Ch.8 p. 383
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class AutoSlotProperties(type):
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def __new__(mcl, classname, bases, dictionary):
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slots = list(dictionary.get("__slots__", []))
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for getter_name in [key for key in dictionary if key.startswith("get_")]:
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name = getter_name
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slots.append("__" + name)
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getter = dictionary.pop(getter_name)
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setter = dictionary.get(setter_name, None)
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if (setter is not None
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and isinstance(setter, collections.Callable)):
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del dictionary[setter_name]
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dictionary[name] = property(getter. setter)
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dictionary["__slots__"] = tuple(slots)
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return super().__new__(mcl, classname, bases, dictionary)
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