python / python/typing

No way to have individual type variable substitutions in uniform tuples of parametrized types

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topic: feature
Dominant language
Python
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Description

Suppose we have:

T = TypeVar('T')
Element = tuple[T]

def fn(elements: tuple[Element, ...]): ...

The problem is that T is forced to be the same for every element, i.e. tuple[tuple[int], tuple[int]] will match, while tuple[tuple[float], tuple[int]] won't. Is there currently any support for this? If not, this would be a worthwhile feature - this would be a big help to get type checking and annotations in ctypes :)

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Research direction

The issue provides no repository file, test, or implementation entry point. Start with the TypeVar/Element example and determine the current behavior for tuple[Element, ...]; a complete contribution would first need an agreed specification, then corresponding implementation and tests.

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Assessment

Tech stack
python
Domain
tooling
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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