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Remain optimistic

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警方虚拟币法律知识的更新

继沿海几座大城市的网警朋友积极学习区块链技术（存证等方面）和相关法律知识之后，内陆的经济警察也开始相关法律知识的更新。

我们发现，浙江某市的区块链内部研讨会议和技术复盘会议中，也出现了警察叔叔参与讨论，而且其对技术本身的研究颇深，出乎大家意料。这与两年前在人民大学与公检法朋友们沟通时的情况（彼时他们对区块链的陌生）形成了鲜明的对比。

这充分说明，已经有案子出现了，并且呈现一定活跃态势，司法机关严阵以待，提前用相关法律知识武装自己，以便更好地适应或许会出现的涉币案件潮。

反观链圈，几乎每一个区块链项目方都有“发币”的冲动，虽然我们理解“激励机制”对项目自身的作用，然而，一旦发币 ICO，在我国现有法律框架下会被定性为“非法的公开融资行为”，涉嫌非法集资类犯罪或非法经营罪等。

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Overview

随着消费者支付习惯的改变，现金的存在作用在不断弱化。无现金交易将成为下一个支付前沿。目前多国央行在筹备发行数字货币，数字货币的稳定性和安全性，是各国央行研发的重中之重。

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状态模式

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let ResultState = (() => {
  let States = {
    state0: function () {
      console.log("state0")
    },
    state1: function () {
      console.log("state1")
    },
    state2: function () {
      console.log("state2")
    },
    state3: function () {
      console.log("state3")
    },
  }

  function show(result) {
    States["state" + result] && States["state" + result]()
  }

  return {
    show,
  }
})()

// for test
ResultState.show(3)

策略模式

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let Price = (() => {
  let obj = {
    return30: (price) => +price + parseInt(price / 100) * 30,
    return50: (price) => +price + parseInt(price / 100) * 50,
    percent90: (price) => (price * 100 * 90) / 10000,
    percent80: (price) => (price * 100 * 80) / 10000,
  }
  return (algorithm, price) => {
    return obj[algorithm] && obj[algorithm](price)
  }
})()

// for test
let price = Price("return50", 321.13)
console.log(price)

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装饰器

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/**
 * 为dom元素添加事件
 * @param {} dom
 * @param {*} type
 * @param {*} fn
 */
function addEvent(dom, type, fn) {
  if (dom.addEventListener) {
    dom.addEventListener(type, fn, false)
  } else if (dom.attachEvent) {
    dom.attachEvent("on" + type, fn)
  } else {
    dom["on" + type] = fn
  }
}

/**
 * 装饰已有对象
 * @param {*} id
 * @param {*} fn
 */
function decorator(id, fn) {
  let obj = document.querySelector(id)
  if (typeof id.onclick === "function") {
    let oldFn = id.onclick
    id.onclick = function () {
      oldFn()
      fn()
    }
  } else {
    obj.onclick = fn
  }
}

观察者模式

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let Observer = (() => {
  let _message = {}
  return {
    regist: function (type, fn) {
      if (typeof _message[type] === "undefined") {
        _message[type] = [fn]
      } else {
        _message[type].push(fn)
      }
    },
    fire: function (type, args) {
      if (!_message[type]) {
        return
      }
      let events = {
        type,
        args: args || {},
      }
      for (let i = 0, len = _message[type].length; i < len; i++) {
        _message[type][i].call(this, events)
      }
    },
    remove: function (type, fn) {
      if (_message[type] instanceof Array) {
        for (let i = _message[type].length - 1; i >= 0; i--) {
          _message[type][i] === fn && _message[type].splice(i, 1)
        }
      }
    },
  }
})()

Observer.regist("test", function (e) {
  // register
  console.log(e.type, e.args.msg)
})
Observer.fire("test", { msg: "this is some test message" }) // send

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惰性单例

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let LazySingle = (() => {
  let instance = null
  function Single() {
    return {
      Method: function () {
        console.log("public method")
      },
      Prototype: "some message",
    }
  }
  return () => {
    if (!instance) instance = Single()
    return instance
  }
})()

// for test
console.log(LazySingle().Prototype)
LazySingle().Method()

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原型模式

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let LoopImages = function (imageArr, container) {
  this.imageArr = imageArr
  this.container = container
}
LoopImages.prototype = {
  createImage: function () {
    console.log("create image")
  },
  changeImage: function () {
    console.log("change image")
  },
}

let SlideLoopImg = function (imageArr, container) {
  LoopImages.call(this, imageArr, container)
}
SlideLoopImg.prototype = new LoopImages() // 继承
SlideLoopImg.prototype.changeImage = () => {
  // 重写
  console.log("slide loop change image")
}

// for test
let slideImage = new SlideLoopImg(["1.jpg", "2.jpg"], "slide")
console.log(slideImage.container)
slideImage.changeImage()

原型继承

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/**
 * copy object
 */
function prototypeExtend() {
  let F = function () {}
  // let F = new Function()

  for (let i = 0; i < arguments.length; i++) {
    for (let j in arguments[i]) {
      F.prototype[j] = arguments[i][j]
    }
  }

  return new F()
}

// for test
let car = prototypeExtend(
  {
    speed: 20,
    fast: function () {
      this.speed++
      console.log("is faster")
    },
  },
  {
    slow: function () {
      this.speed--
      console.log("is slower")
    },
  },
  {
    stop: function () {
      this.speed = 0
      console.log("is stop")
    },
  },
  {
    currentSpeed: function () {
      console.log(this.speed)
    },
  }
)

car.fast()
car.fast()
car.fast()
car.fast()

car.currentSpeed()
car.stop()

car.currentSpeed()

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let Human = function (param) {
  this.skill = (param && param.skill) || "null"
  this.hobby = (param && param.skill) || "null"
}
Human.prototype = {
  getSkill: function () {
    return this.skill
  },
  getHobby: function () {
    return this.hobby
  },
}

let Named = function (name) {
  let _this = this
  ;((name, _this) => {
    this.wholeName = name
    if (name.indexOf(" ") > -1) {
      _this.FirstName = name.slice(0, name.indexOf(" "))
      _this.LastName = name.slice(name.indexOf(" "))
    }
  })(name, _this)
}

let Work = function (work) {
  let _this = this
  ;((work, _this) => {
    switch (work) {
      case "code":
        this.work = "developer"
        break
      case "design":
        this.work = "designer"
        break
      default:
        this.work = work
    }
  })(work, _this)
}

Work.prototype.changeWork = function (work) {
  this.work = work
}

/**
 * to create a Person
 * @param {*} name
 * @param {*} work
 */
let Person = function (name, work) {
  let _person = new Human()
  _person.name = new Named(name)
  _person.work = new Work(work)
  return _person
}

// for test
let person = new Person("Jack Edward", "design")
console.log(person.work)
console.log(person.name)
person.work.changeWork("code")
console.log(person.work)

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工厂模式

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let Basketball = function () {
  this.name = 'basketball'
}
Basketball.prototype = {
  getMember: function () {
    console.log(5)
  },
  getBallSize: function () {
    console.log('big')
  },
}

let FootBall = function () {
  this.name = 'football'
}
FootBall.prototype = {
  getMember: function () {
    console.log(11)
  },
  getBallSize: function () {
    console.log('big')
  },
}

let Tennis = function () {
  this.name = 'tennis'
}
Tennis.prototype = {
  getMember: function () {
    console.log(1)
  },
  getBallSize: function () {
    console.log('small')
  },
}

let SportFactory = function (name) {
  switch (name) {
    case 'basketball':
      return new Basketball()
    case 'football':
      return new FootBall()
    case 'tennis':
      return new Tennis()
  }
}

let footBall = new SportFactory('football')
footBall.getMember()
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// Product base attribute
interface Product {
  operation(): string
}

class ConcreteProduct1 implements Product {
  public operation(): string {
    return 'This is Product1'
  }
}
class ConcreteProduct2 implements Product {
  public operation(): string {
    return 'This is Product2'
  }
}

abstract class Creator {
  public abstract factoryMethod(): Product

  public operation(): string {
    const product = this.factoryMethod()

    return product.operation()
  }
}

class ConcreteCreator1 extends Creator {
  public factoryMethod(): Product {
    return new ConcreteProduct1()
  }
}
class ConcreteCreator2 extends Creator {
  public factoryMethod(): Product {
    return new ConcreteProduct2()
  }
}

// usage
function clientCode(creator: Creator) {
  console.log(creator.operation())
}

clientCode(new ConcreteCreator1())
clientCode(new ConcreteCreator2())

安全工厂

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let Factory = function (type, content) {
  if (this instanceof Factory) {
    // check if is instance Factory
    return new this[type](content)
  } else {
    return new Factory(type, content)
  }
}
Factory.prototype = {
  Java: function (content) {
    console.log(content)
  },
  JavaScript: function (content) {
    console.log(content)
  },
}

let data = [
  {
    type: 'Java',
    content: 'This is Java',
  },
  {
    type: 'JavaScript',
    content: 'This is JavaScript',
  },
]

// for test
for (let i = 0; i < data.length; i++) Factory(data[i].type, data[i].content)

抽象工厂

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/**
 * to extend superType
 * @param {*} subType
 * @param {*} superType
 */
let VehicleFactory = (subType, superType) => {
  if (typeof VehicleFactory[superType] === 'function') {
    function F() {}
    F.prototype = new VehicleFactory[superType]()
    subType.constuctor = subType
    subType.prototype = new F()
  } else {
    throw new Error("don' not have this abstract class")
  }
}

// create base class
VehicleFactory.Car = function () {
  this.type = 'car'
}
VehicleFactory.Car.prototype = {
  getPrice: function () {
    return new Error('abstract')
  },
  getSpeed: function () {
    return new Error('abstract')
  },
}

let BMW = function (price, speed) {
  this.price = price
  this.speed = speed
}
VehicleFactory(BMW, 'Car') // interface
BMW.prototype = {
  getPrice: function () {
    return this.price
  },
  getSpeed: function () {
    return this.speed
  },
}

// for test
let myBmw = new BMW(10000, 100)
console.log(myBmw.getPrice())
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// product interface
interface AbstractProductA {
  functionA(): string
}

interface AbstractProductB {
  /**
   * base operation
   * @return {string}
   */
  functionA(): string

  /**
   * inject some operation
   * @param {AbstractProductA} product
   * @return {string}
   */
  functionB(product: AbstractProductA): string
}

// concrete production
class ConcreteProductA1 implements AbstractProductA {
  functionA(): string {
    return 'This is functionA from ProductA1'
  }
}
class ConcreteProductA2 implements AbstractProductA {
  functionA(): string {
    return 'This is functionA from ProductA2'
  }
}
class ConcreteProductB1 implements AbstractProductB {
  functionA(): string {
    return 'This is functionA from ProductB1'
  }

  functionB(product: AbstractProductA): string {
    return 'Function B2: ' + product.functionA()
  }
}
class ConcreteProductB2 implements AbstractProductB {
  functionA(): string {
    return 'This is functionA from ProductB2'
  }

  functionB(product: AbstractProductA): string {
    return 'Function B2: ' + product.functionA()
  }
}

// factory interface
interface AbstractFactory {
  createProductA(): AbstractProductA
  createProductB(): AbstractProductB
}

// concrete factory
class ConcreteFactory1 implements AbstractFactory {
  createProductA(): AbstractProductA {
    return new ConcreteProductA1()
  }

  createProductB(): AbstractProductB {
    return new ConcreteProductB1()
  }
}
class ConcreteFactory2 implements AbstractFactory {
  createProductA(): AbstractProductA {
    return new ConcreteProductA2()
  }

  createProductB(): AbstractProductB {
    return new ConcreteProductB2()
  }
}

// usage
/**
 * use with different facotry.
 * @param {AbstractFactory} factory
 */
function clientCode(factory: AbstractFactory) {
  const productA = factory.createProductA()
  const productB = factory.createProductB()

  console.log(productB.functionA())
  console.log(productB.functionB(productA))
}

clientCode(new ConcreteFactory1())
clientCode(new ConcreteFactory2())

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子类的原型对象-类式继承

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// 类式继承
// parent
function SuperClass() {
  this.superValue = true
}
SuperClass.prototype.getSuperValue = function () {
  return this.superValue
}

// child
function SubClass() {
  this.subValue = false
}
SubClass.prototype = new SuperClass()
SubClass.prototype.getSubValue = function () {
  return this.subValue
}

let child = new SubClass()
console.log(child.getSuperValue()) // true
console.log(child.getSubValue()) // false
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