there's a new type argument syntax for functions and classes

def max[T](args: Iterable[T]) -> T:
    pass

class list[T]:
    def __getitem__(self, index: int, /) -> T:
        pass

    def append(self, element: T) -> None:
        pass

Resources:

• https://docs.python.org/3/reference/compound_stmts.html#generic-classes
• https://docs.python.org/3/reference/compound_stmts.html#generic-functions
• https://peps.python.org/pep-0695/
• https://docs.python.org/3/whatsnew/3.12.html#whatsnew312-pep695
• Related issue: Support type alias syntax PEP 695 (Python 3.12) #18

See also screenshot in lezer playground by @dralletje, this completely throws off the parser (it thinks it's an array, and it breaks down).

I must say I'm impressed by CM+Lezer at how very well everything recovers.