Can Typescript ensure arrays have a repeating type pattern? e.g. [string, number, string, number, ....(forever)]

Question

I have a function, which I want to ensure takes a string, followed by a number. And optionally, more string number pairs. So like a tuple, but "infinite" times:

const fn = (...args: [string, number] |
[string, number, string, number] |
[string, number, string, number, string, number] |
[string, number, string, number, string, number, string, number] | ...etc etc) => {}

and so on

An alternative psuedo type construction:

type Pair = [string, number, ...Pair];

Is this possible with TypeScript?

EDIT This looks like it should work, but doesn't. TypeScript does not seem to infer the order of the pairs correctly.

type Pair = [string, number, ...Pair[]];

Answer 1

I believe so. You would define the type as

type RecurringTuple = [string, number, RecurringTuple[]];
const fn = (...args: RecurringTuple) => {}

Haven't tested, but found a similar case in this link.