Dual use destructurable

createDualUseDestructurable.ts

/**
 * Creates a return value that is destructurable as both an object and an array.
 *
 * Usage example:
 *
 * ```ts
 * const obj = createDualUseDestructurable({ foo, bar } as const, [ foo, bar ] as const)
 * let { foo, bar } = obj
 * let [ foo, bar ] = obj
 * ```
 *
 * @param obj An object
 * @param arr An array
 * @returns Object that can also be destructured as an array
 */
export function createDualUseDestructurable<
  T extends Record<string, unknown>,
  A extends readonly any[],
>(obj: T, arr: A): T & A {
  const clone = { ...obj }

  Object.defineProperty(clone, Symbol.iterator, {
    enumerable: false,
    value() {
      let index = 0
      return {
        next: () => ({
          value: arr[index++],
          done: index > arr.length,
        }),
      }
    },
  })

  return clone as T & A
}