 class MyURLSearchParams {   /**    * @params {string} init    */   constructor(init) {     this.store = this.parse(init);   }   parse(string) {    const str = string[0] === '?' ? string.substring(1) : string;    const pairs = str.split('&');    const list = [];    for(const pair of pairs) {      list.push(pair.split('='));    }    return list;   }      /**     * @params {string} name    * @params {any} value    */   append(name, value) {     this.store.push([name, String(value)]);   }      /**    * @params {string} name    */   delete(name) {     this.store = this.store.filter(([key]) => key !== name);   }      /**    * @returns {Iterator}     */   * entries() {    yield* this.store;   }      /**    * @param {(value, key) => void} callback    */   forEach(callback) {     for(const [key, val] of this.store) {      try {        callback(val, key);      } catch (e) {        console.error(e);      }     }   }      /**    * @param {string} name    * returns the first value of the name    */   get(name) {    for(const val of this.store) {      if (val[0] === name) {        return val[1];      }    }    return null;   }      /**    * @param {string} name    * @return {string[]}    * returns the value list of the name    */   getAll(name) {     return this.store.filter(([key]) => key === name).map(([, val]) => val);   }      /**    * @params {string} name    * @return {boolean}    */   has(name) {     for(const val of this.store) {      if (val[0] === name) {        return true;      }     }     return false;   }      /**    * @return {Iterator}    */   keys() {     return this.store.map(([key]) => key).entries();   }      /**    * @param {string} name    * @param {any} value    */   set(name, value) {    const newStore = [];    let hasSetNewValue = false;    for(let i=0; i<this.store.length; i++) {      if (this.store[i][0] === name && !hasSetNewValue) {        hasSetNewValue = true;        newStore.push([name, String(value)]);      } else if (this.store[i][0] !== name) {        newStore.push(this.store[i]);      }    }    if (!hasSetNewValue) {      newStore.push([name, String(value)]);    }    this.store = newStore;   }      // sor all key/value pairs based on the keys   sort() {     this.store.sort((a, b) => a[0].localeCompare(b[0]));   }      /**    * @return {string}    */   toString() {     return this.store.map(pair => pair.join('=')).join('&');   }      /**    * @return {Iterator} values    */   * values() {    yield* this.store.map(([, val]) => val);   } }