import type { WritableAry } from ".";
import type { Args, GenericFn, GenericResolver } from "../HKT";

/**
 * Build a writable array from a type.
 *
 * Sig: `<T>(x: T) => Array<T>`
 *
 * @example
 * ```typescript
 * type R1 = OfWritable<number>;
 * //   ^?: number[]
 * type R2 = OfWritable<42 | string>;
 * //   ^?: (42 | string)[]
 * ```
 */
export type OfWritable<T> = T[];

interface Resolver extends GenericResolver<[unknown], WritableAry<unknown>> {
  on1: ([x]: Args<this>) => [[], WritableAry<typeof x>];
}

/**
 * [Fn] Build a writable array from a type.
 *
 * Sig: `<T>(x: T) => Array<T>`
 */
export default interface OfWritableFn extends GenericFn<Resolver> {
  def: ([x]: Args<this>) => OfWritable<typeof x>;
}