Infer tuple type instead of union type

Question

Does anybody know how to make compiler to infer tuple type automatically ?

// Now: (string | number)[]
// Wanted: [string, number][]
const x = [ [\"a\", 2],          


        

Answer 1

The compiler does not infer that, and there no way to force it to "know" it. the only thing that you can (And should do) is defined an interface that extends Array. like this:

interface NumStrTuple extends Array {
    0: number;
    1: string;
    length: 2;
}

And use it to define your const like this:

const x: NumStrTuple = [ ["a", 2], ["b", 2] ];