[sssxks]

The deleted explanation hints an specific design ("no annotation, no check") that by
test only exists in mypy. I tested a few checkers on the following example, and
doesn't match the document at all. therefore, it should be deleted.

from typing import Any


class Unannotated:
    def __init__(self):
        self.value = 1 + "a"


class UnannotatedParameter:
    def __init__(self, x):
        self.value = 1 + "a"


class ReturnAnnotated:
    def __init__(self) -> None:
        self.value = 1 + "a"


class AnyParameter:
    def __init__(self, x: Any):
        self.value = 1 + "a"


class TypedParameter:
    def __init__(self, x: int):
        self.value = 1 + "a"

ctor sig	mypy default	mypy --check-untyped-defs	Pyright default	ty default	Pyrefly --preset default
__init__(self)	Misses	Catches	Catches	Catches	Catches
__init__(self, x)	Misses	Catches	Catches	Catches	Catches
__init__(self) -> None	Catches	Catches	Catches	Catches	Catches
__init__(self, x: Any)	Catches	Catches	Catches	Catches	Catches
__init__(self, x: int)	Catches	Catches	Catches	Catches	Catches

[python-cla-bot]

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