Examples of JS data analysis data deduplication and parameter serialization

const set = new Set([2, 8, 3, 8, 5])

const uniqueness = (data, key) => {
  const hash = new Map()
  return (item => !(item[key]) && (item[key], 1))
}

/**
 * @description: Convert object to query string
 * @params {Object} data: Source data
 * @return {String} Target data
 * @example
 *
 * serialize({ a: 1, b: 2 })
 *
 * a=1&b=2
 */

export const serialize = data => {
  return (data).map(key => `${encodeURIComponent(key)}=${encodeURIComponent(data[key])}`).join('&')
}

/**
 * @description: Get query parameters
 * @params {String} name: query parameter name
 * @return {String} Target data
 * @example
 *
 * getQueryString('id')
 */

export const getQueryString = key => {
  return (new URLSearchParams()).get(key)
}

class Route {
  static url = new URL(location)
  static attr(attribute) {
    return [attribute]
  }
  static getParams() {
    const { searchParams } = , params = {}
    for (const [key, value] of ()) {
      params[key] = value
    }
    return params
  }
  static getParam(name) {
    const { searchParams } = 
    return (name)
  }
  static hasParam(name) {
    const { searchParams } = 
    return (name)
  }
}