Feature or enhancement

Add a newfrozen_default parameter todataclass_transform similar to the existingeq_default andorder_default parameters.

Pitch

• Frozen dataclasses are very popular when working with Jax (flax.struct.dataclass andtjax.dataclass), so being able to indicate that they are frozen by default would improve the user experience.
• dataclass_transform is currently supported by Pyright/Pylance and Pyre. Both teams are in favor of implementing this new parameter. Sincedataclass_transform supports kwargs for experimentation/extensibility, Pyright was already able toadd support forfrozen_default.
• All feedback on typing-sig has been in favor of this enhancement.

Previous discussion

Discussed intyping-sig.

Linked PRs

• gh-99957: Addfrozen_default parameter ondataclass_transform #99958