Variadic type functions do not receive the type arguments

[Niki4tap]

I tried this code:

type function variadic_type_fn(...)
	print(...)
	print(#{...})
	return types.string
end

local _: variadic_type_fn<() -> any> = "hello"

... in type function code appears to always expand to nothing, no matter what arguments are provided.

Output from luau-analyze:

./test.luau(7,10): TypeError:
./test.luau(7,10): TypeError: 0

With --!strict, this also prints: TypeError: Generic type 'variadic_type_fn' expects 0 type arguments, but 1 is specified

I looked at the RFC, and I don't think it mentions anything about variadics, or restricting type function signatures, so I assume this should work.

[vegorov-rbx]

In this case, being underspecified means that it is not supported and the required design is missing on how variadic arguments and types/packs interact and are handled by type functions.
Specifying the behavior is likely to require an RFC.

Type function signatures are unrestricted because type functions can call each other just fine.