Tuple to Union

introduction#

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

For example

ts
type Arr = ['1', '2', '3']
const a: TupleToUnion<Arr> // expected to be '1' | '2' | '3'

ts
type Arr = ['1', '2', '3']
const a: TupleToUnion<Arr> // expected to be '1' | '2' | '3'

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start point#

ts
/* _____________ Your Code Here _____________ */
 
type TupleToUnion<T> = any
 
/* _____________ Test Cases _____________ */
type cases = [
  Expect<Equal<TupleToUnion<[123, '456', true]>, 123 | '456' | true>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.  Expect<Equal<TupleToUnion<[123]>, 123>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.]Try

ts
/* _____________ Your Code Here _____________ */
 
type TupleToUnion<T> = any
 
/* _____________ Test Cases _____________ */
type cases = [
  Expect<Equal<TupleToUnion<[123, '456', true]>, 123 | '456' | true>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.  Expect<Equal<TupleToUnion<[123]>, 123>>,
Type 'false' does not satisfy the constraint 'true'.2344Type 'false' does not satisfy the constraint 'true'.]Try

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my solutions#

Spoiler warning // Click to reveal answer

ts
type TupleToUnion<T extends any[]> = T[number]Try

ts
type TupleToUnion<T extends any[]> = T[number]Try

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