types converter

to.ts

/**
 * This is helper class for parse server response
 */
export class To {

  public static number(raw: any): number {
    const n = Number(raw);
    return raw === undefined || raw === null || isNaN(n) ? null : n;
  }

  public static boolean(raw: any): boolean {
    return raw === undefined || raw === null ? null : Boolean(Number(raw));
  }

  public static string(raw: any): string {
    return raw === undefined || raw === null ? null : String(raw);
  }

  public static object(raw: any): object {
    return raw === undefined || raw === null || raw instanceof Object === false ? null : raw;
  }

  public static array<T extends any>(raw: any): Array<T> {
    return raw === undefined || raw === null || raw instanceof Array === false ? null : raw;
  }

  public static empty<T, R>(raw: R, cb: {(raw: R): T}): T | R {
    return raw === undefined || raw === null ? null : (cb instanceof Function ? cb(raw) : raw);
  }

}