Wrong type inferred for array of tuples

[chinhodado]

TypeScript Version: 3.1.6

Search Terms:
array tuple inference inferred argument

Code

let x = [["a", [1]]];

function f(arg: [string, number[]][]) {
}

f(x);

// If I declare x's type directly like this then it works:
// let x: [string, number[]][] = [["a", [1]]];

Expected behavior:
No error

Actual behavior:
Error:

Error:(352, 3) TS2345: Argument of type '(string | number[])[][]' is not assignable to parameter of type '[string, number[]][]'.
  Type '(string | number[])[]' is not assignable to type '[string, number[]]'.
    Property '0' is missing in type '(string | number[])[]'.

Playground Link:
Link

[DanielRosenwasser]

Duplicate of #20899 and duplicate of #3369.

[ahejlsberg]

Also see my comment here.

[chinhodado]

I see, thank you for the quick response!

[typescript-bot]

This issue has been marked as a duplicate and has seen no activity in the last day. It has been closed for automatic house-keeping purposes.