craftbeerpi4-pione/venv3/lib/python3.7/site-packages/aiohttp/_helpers.pyx

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Cython
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2021-03-03 23:49:41 +01:00
cdef class reify:
"""Use as a class method decorator. It operates almost exactly like
the Python `@property` decorator, but it puts the result of the
method it decorates into the instance dict after the first call,
effectively replacing the function it decorates with an instance
variable. It is, in Python parlance, a data descriptor.
"""
cdef object wrapped
cdef object name
def __init__(self, wrapped):
self.wrapped = wrapped
self.name = wrapped.__name__
@property
def __doc__(self):
return self.wrapped.__doc__
def __get__(self, inst, owner):
try:
try:
return inst._cache[self.name]
except KeyError:
val = self.wrapped(inst)
inst._cache[self.name] = val
return val
except AttributeError:
if inst is None:
return self
raise
def __set__(self, inst, value):
raise AttributeError("reified property is read-only")