Feedback for name2type mapping

[guettli]

Dear mypy developers,

I am looking for feedback for this little idea:

https://github.com/guettli/python-name2type-mapping

Please tell me what you think.

Python name2type mapping

In October 2018 on the mailing list python-ideas some developers encouraged me, that the idea of a name2type mapping would be usefull.

Goal:

• Better type-hints in IDEs.

This is not the goal:

• Type-hints which get used during run-time.

Syntax Proposal

The name2type mapping is defined in the docstring of a Python file.

The general syntax is "name2type:" followed by a comma sperated list of variable names. Then ":", then the type hint.

Examples::

 """
 name2type: my_int, my_number, ....: int
 name2type: request*: django.http.HttpRequest
 """"

If the docstring is in a file called __init__.py, then the type hints get specified for all files below this directory (recursively).

[ilevkivskyi]

I think this belongs rather to stubgen (maintained here), or to PyAnnotate (in a separate repo), rather than to mypy itself. Otherwise such feature might have some weird action at a distance. Also explicit is better than implicit.

[gvanrossum]

Yeah, there is now a whole repo dedicated to discussion of this idea, no need to have a separate discussion in any of the mypy projects.