Base class for protocol classes. Protocol classes are defined as::
tfds.typing.Protocol(
*args, **kwds
)
class Proto(Protocol):
def meth(self) -> int:
...
Such classes are primarily used with static type checkers that recognize structural subtyping (static duck-typing), for example::
class C:
def meth(self) -> int:
return 0
def func(x: Proto) -> int:
return x.meth()
func(C()) # Passes static type check
See PEP 544 for details. Protocol classes decorated with @typing_extensions.runtime act as simple-minded runtime protocol that checks only the presence of given attributes, ignoring their type signatures.
Protocol classes can be generic, they are defined as::
class GenProto(Protocol[T]):
def meth(self) -> T:
...