Re: Recursive type annotations

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From	Ian Kelly <ian.g.kelly@gmail.com>
Newsgroups	comp.lang.python
Subject	Re: Recursive type annotations
Date	Wed, 8 Jun 2016 08:58:22 -0600
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On Wed, Jun 8, 2016 at 7:31 AM, Nagy László Zsolt <gandalf@shopzeus.com> wrote:
>
>>>         pass
>>>
>>> NameError: name 'Test' is not defined
>> I think you can fix this by using a string annotation as follows:
>>
>>     class Test:
>>         def test(self, child: "Test"):
>>             pass
> Yes, you are right. It is not directly written in the official
> documentation ( https://docs.python.org/3/library/typing.html ), but it
> is in the PEP 0484, section "Forward references".

That link specifically documents the typing module. Forward references
don't really have anything to do with the typing module and are best
covered by the documentation of the static checker in use. Here's
where the MyPy documentation covers it:

http://mypy.readthedocs.io/en/latest/kinds_of_types.html#class-name-forward-references

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Thread

Recursive type annotations Nagy László Zsolt <gandalf@shopzeus.com> - 2016-06-08 15:02 +0200
  Re: Recursive type annotations Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2016-06-08 13:11 +0000
    Re: Recursive type annotations Nagy László Zsolt <gandalf@shopzeus.com> - 2016-06-08 15:31 +0200
    Re: Recursive type annotations Ian Kelly <ian.g.kelly@gmail.com> - 2016-06-08 08:58 -0600

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