#10Medium

Tuple to Union

Implement a generic `TupleToUnion<T>` which covers the values of a tuple to its values union. Learn conditional types with `infer`, union type manipulation, tuple manipulation in this medium-level challenge on TypeScriptPro.

In this medium-level challenge, you'll implement a generic TupleToUnion<T> which converts the values of a tuple to a union.

Challenge Instructions: Tuple to Union

Medium

Implement a generic TupleToUnion<T> which covers the values of a tuple to its values union.

For example

type Arr = ['1', '2', '3']
 
type Test = TupleToUnion<Arr> // expected to be '1' | '2' | '3'

Change the following code to make the test cases pass (no type check errors).

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Video Walkthrough

Detailed Explanation

To convert a tuple to a union, we use indexed access:

[object Object]

How it works:

T[number] accesses all numeric indices of the tuple - this produces a union of all tuple element types.

This challenge is originally from here.

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