There is no reason to have else

[lgalfaso]

Given that these work:

let length = vector => match (vector) {
    { x, y, z }: Math.sqrt(x ** 2 + y ** 2 + z ** 2),
    { x, y }:   Math.sqrt(x ** 2 + y ** 2),
}

Then there is no reason why this would not work

let length = vector => match (vector) {
    { x, y, z }: Math.sqrt(x ** 2 + y ** 2 + z ** 2),
    { x, y }:   Math.sqrt(x ** 2 + y ** 2),
    x: x,
}

[7fe]

I believe this has been discussed in more then one place #25

[lgalfaso]

@limeblack agree, closing it.