Myanmar Phone Number validation & normalization

MMPhoneNumber.js

// Myanmar Phone Number validation & normalization for ES6 
// Based on https://github.com/trhura/mm_phonenumber

const mobileCode = "(0?9)";
const countryCode = "(\\+?95)";
const ooredooNumber = "(?:9(?:7|6)\\d{7})";
const telenorNumber = "(?:7(?:9|8|7|6)\\d{7})";
const mptNumber =
  "(?:5\\d{6}|4\\d{7,8}|2\\d{6,8}|3\\d{7,8}|6\\d{6}|8\\d{6}|7\\d{7}|9(?:0|1|9)\\d{5,6})";
const allOperators = `(${ooredooNumber}|${telenorNumber}|${mptNumber})$`;
const mmNumber = `^${countryCode}?${mobileCode}?${allOperators}`;

export class MMPhoneNumber {
  static isValid(number) {
    let phone = number.toString();
    return phone.match(mmNumber) != null;
  }

  static normalize(number) {
    let phone = number.toString();
    let matches = phone.match(mmNumber);

    if (matches == null) {
      throw new TypeError(`${number} is not a valid phone number.`);
    }

    return parseInt("959" + matches[3]);
  }
}