FWIW, Obj-C doesn't have keyword arguments. It just has infix method names. But all arguments in an Obj-C method are required, and the order is significant.
Similarly, in Swift, the order of defaulted arguments is significant. So you wouldn't see anyone do something like that crazy matplotlib method in Swift, because remembering the order of all the arguments in that function is impractical.
Yeah when we do named args it will very likely be based on Swift, but a bit different due to backwards compat and the desire to integrate it into existing methods like Vec::from_raw_parts and ptr::copy.
It's very clear there...