def __call__(cls, *args, **kwargs):
signature = inspect.signature(cls.__init__)
positional_in_kwargs = [
p.name for p in signature.parameters.values()
if p.kind == p.POSITIONAL_OR_KEYWORD and p.default == p.empty
and p.name in kwargs
]
if positional_in_kwargs:
warn(f"Positional arguments {positional_in_kwargs} were "
f"supplied as keyword arguments to "
f"{cls.__init__}{signature}. "
f"This may create separate Multiton instances "
f"for what is intended to be a unique set of "
f"arguments.")
key = freeze(args + (kwargs if kwargs else Multiton.MISSING, ))
# Double-checked locking
# https://en.wikipedia.org/wiki/Double-checked_locking
try:
return cls.__cache[key]
except KeyError:
pass
with cls.__lock:
try:
return cls.__cache[key]
except KeyError:
instance = type.__call__(cls, *args, **kwargs)
cls.__cache[key] = instance
return instance
def __hash__(self):
return hash(
freeze(
(
self.url,
self.storage_options,
)
)
)
def __hash__(self):
return hash((
self.type,
self.dims,
self.dtype,
self.chunks,
self.shape,
freeze(self.attrs),
))
def __call__(cls, *args, **kwargs):
key = freeze((cls, ) + args + (kwargs, ))
try:
return _dataset_cache[key]
except KeyError:
with _dataset_lock:
try:
return _dataset_cache[key]
except KeyError:
instance = type.__call__(cls, *args, **kwargs)
_dataset_cache[key] = instance
return instance
def __hash__(self):
return hash(freeze((self.data_vars, self.coords, self.attrs)))