TypeAliasType aliases (jax.py/numpy.py/torch.py/cupy.py) break pyright under Python 3.10/3.11 despite requires-python >=3.10

[nstarman]

Summary

bearshape's predefined array-type aliases (Shaped, Bool, I8…C128, Int, Integer, Float, etc., and the *Like variants) are defined via typing.TypeAliasType(...) inside if tp.TYPE_CHECKING: blocks in bearshape/jax.py, numpy.py, torch.py, and cupy.py (e.g. jax.py:234-265):

if tp.TYPE_CHECKING:
  Shaped = tp.TypeAliasType("Shaped", JaxArray, type_params=(_Dims,))
  ...

typing.TypeAliasType (PEP 695) was only added to the stdlib in Python 3.12. bearshape declares requires-python = ">=3.10", so this is inconsistent with the package's own supported floor: any static type checker resolving Python 3.10 or 3.11 against these modules breaks.

Reproduction

With bearshape==0.0.1 installed under Python 3.11:

pyright --pythonversion 3.11 path/to/file_using_bearshape_types.py

produces, on every line that subscripts one of these types (e.g. Shaped[Array, "N"]):

error: Variable not allowed in type expression (reportInvalidTypeForm)

Re-running with --pythonversion 3.13 produces 0 errors for the same file — confirming this is purely a Python-version resolution issue in how these aliases are declared, not a usage error on the consumer's side.

This can silently escape a project's own CI if its pyright pre-commit hook (or any pinned pyright/mypy invocation) resolves a newer interpreter than the project's declared floor — the gap only surfaces when a downstream project explicitly checks at its own minimum supported Python version.

Suggested fix

Use the standard typing_extensions backport instead of typing.TypeAliasType when targeting <3.12, e.g.:

import typing_extensions as tpe

if tp.TYPE_CHECKING:
  Shaped = tpe.TypeAliasType("Shaped", JaxArray, type_params=(_Dims,))

across jax.py, numpy.py, torch.py, and cupy.py. This would need adding typing_extensions as a runtime dependency (only exercised under TYPE_CHECKING, so effectively type-checker-only, but still needs to resolve for tools like pyright/mypy) — currently bearshape only declares beartype>=0.20,<0.23.

For reference, quax hit the identical issue for a local TypeAliasType alias and fixed it the same way (swap typing.TypeAliasType → typing_extensions.TypeAliasType), which is what prompted this report.

Happy to open a PR with this change across the four modules if useful.