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https://github.com/avatao-content/baseimage-tutorial-framework
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28 lines
698 B
Python
28 lines
698 B
Python
from functools import update_wrapper, wraps
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class lazy_property:
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"""
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Decorator that replaces a function with the value
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it calculates on the first call.
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"""
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def __init__(self, func):
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self.func = func
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update_wrapper(self, func)
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def __get__(self, instance, owner):
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if instance is None:
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return self # avoids potential __new__ TypeError
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value = self.func(instance)
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setattr(instance, self.func.__name__, value)
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return value
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def lazy_factory(fun):
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class wrapper:
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@wraps(fun)
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@lazy_property
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def instance(self): # pylint: disable=no-self-use
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return fun()
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return wrapper()
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