js-generator-状态机及控制状态机_js 状态机

使用一个变量维护状态

let open = true
let clock = () => {
  open = !open
  return !open
}
console.log(clock())
console.log(clock())

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使用generator自身状态

let clock2 = function* () {
  while(true) {
    yield true
    yield false
  }
}
let gen = clock2()
console.log(gen.next().value)
console.log(gen.next().value)
console.log(gen.next().value)
console.log(gen.next().value)
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控制状态机1:使用互相来控制

let clock3 = function* () {
  let r
  while(r = (yield 'isOpen?')) {
    yield true
    yield false
  }
}
let r
let gen = clock3()
gen.next() // 启动
r = gen.next(1) // t 开启
console.log(r.value)
r = gen.next() // f
console.log(r.value)
r = gen.next() // ask
console.log(r.value)
r = gen.next(1) // t 开启
console.log(r.value)
r = gen.next() // f
console.log(r.value)
r = gen.next() // ask
console.log(r.value)
r = gen.next(0) // 关闭
console.log(r.value)
r = gen.next() // undefined
console.log(r.value)
r = gen.next() // undefined
console.log(r.value)
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控制状态机2:使用return来控制

let clock4 = function* () {
  while(true) {
    yield true
    yield false
  }
}
let r
let gen = clock4()
r = gen.next() // t
console.log(r.value)
r = gen.next() // f
console.log(r.value)
r = gen.return() // undefined
console.log(r.value)
r = gen.next() // undefined
console.log(r.value)
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