tuples_type_form_2 error

Invalid tuple type syntax

Validates tuple type annotations according to PEP 646 rules:

- tupleT, ... must have exactly one type before ... - tuple... is invalid (must specify a type) - tupleT, ..., U is invalid (... can only appear at the end) - tupleT, U, ... is invalid (can't have multiple fixed types before ...) - Invalid unpack patterns like tuple*tuple[str, ...]

t1: tuple[int, ...]        # OK
t2: tuple[int, int, ...]   # E — multiple fixed types before ...
t3: tuple[...]             # E — missing type before ...
t4: tuple[..., int]         # E — ... must be at the end
t5: tuple[int, ..., int]    # E — ... must be at the end
t6: tuple[*tuple[str], ...] # E — invalid unpack pattern

How to handle it

Every rule is on by default — strict is the default, not a cage. You can dial tuples_type_form_2 down per-file or per-path from your editor or pyproject.toml, or fix the code so it type-checks. See the Type System rules and the complete diagnostic reference.

Canonical URL: https://www.basilisk-python.dev/errors/tuples_type_form_2