题目如下：
实现一个LazyMan，可以按照以下方式调用:
LazyMan(“Hank”)输出:
Hi! This is Hank! LazyMan(“Hank”).sleep(10).eat(“dinner”)输出
Hi! This is Hank!
//等待10秒..
Wake up after 10
Eat dinner~ LazyMan(“Hank”).eat(“dinner”).eat(“supper”)输出
Hi This is Hank!
Eat dinner~
Eat supper~ LazyMan(“Hank”).sleepFirst(5).eat(“supper”)输出
//等待5秒
Wake up after 5
Hi This is Hank!
Eat supper 以此类推。
实现代码如下：
function _LazyMan(name) {
this.tasks = [];
var self = this;
var fn =(function(n){
var name = n;
return function(){
console.log("Hi! This is " + name + "!");
self.next();
}
})(name);
this.tasks.push(fn);
setTimeout(function(){
self.next();
}, 0); // 在下一个事件循环启动任务
}
/* 事件调度函数 */
_LazyMan.prototype.next = function() {
var fn = this.tasks.shift();
fn && fn();
}
_LazyMan.prototype.eat = function(name) {
var self = this;
var fn =(function(name){
return function(){
console.log("Eat " + name + "~");
self.next()
}
})(name);
this.tasks.push(fn);
return this; // 实现链式调用
}
_LazyMan.prototype.sleep = function(time) {
var self = this;
var fn = (function(time){
return function() {
setTimeout(function(){
console.log("Wake up after " + time + "s!");
self.next();
}, time * 1000);
}
})(time);
this.tasks.push(fn);
return this;
}
_LazyMan.prototype.sleepFirst = function(time) {
var self = this;
var fn = (function(time) {
return function() {
setTimeout(function() {
console.log("Wake up after " + time + "s!");
self.next();
}, time * 1000);
}
})(time);
this.tasks.unshift(fn);
return this;
}
/* 封装 */
function LazyMan(name){
return new _LazyMan(name);
}
举栗子：
LazyMan('Hank').sleepFirst(5).eat('supper')
// _LazyMan {tasks: Array(3)}
// Wake up after 5s!
// Hi! This is Hank!
// Eat supper~
LazyMan('Hank').eat('dinner').eat('supper')
//_LazyMan {tasks: Array(3)}
// Hi! This is Hank!
// Eat dinner~
// Eat supper~
From: http://web.jobbole.com/89626/