编辑代码

function* idMaker() {
    var index = 0
    while (index <3) {
        yield index++
    }
}

var gen = idMaker()
console.log(gen.next())
console.log(gen.next())
console.log(gen.next())
console.log(gen.next())
console.log(gen.next())
console.log(gen.next())