Trivial

能有空、有心思在这里唠叨，大概最近很不爽吧。可以事实上并没有什么人惹我，只是觉得朋友圈挺无聊不适合发些内心中的想法。

Little tips and tricks in JavaScript, but often to use

To do clone for any object in JavaScript will not be simple or straightforward. You will run into the problem of erroneously picking up attributes from the object’s prototype that should be left in the prototype and not copied to the new instance. If, for instance, you are adding a clone method to Object.prototype, as someone depict, you will need to explicitly skip that attribute. But what if there are other additional methods added to Object.prototype, or other intermediate prototypes, that you don’t know about? In that case, you will copy attributes you shouldn’t, so you need to detect unforeseen, non-local attributes with the hasOwnProperty method.

Using tampermonkey to fill studylink automatically which used a lot of jquery api, this is a good backup to remind the usage of a practical scenario.

There are several answers here how to check if a property exists in an object.

I was always using

if(myObj.hasOwnProperty(‘propName’))
but I wonder if there is any difference from
if(‘propName’ in myObj){

NSNumber and NSDictionary are the basic class and most useful class in objective c.

自执行函数写法很诡异，mark一下，需要学习。

在使用polyv的web上传插件时遇到语言问题，官方插件是中文没有切换英文的借口。想到保存到本地修改后使用。
幸好提供了jsonp借口，但是在调用上踩了一下坑。

Promise Simple Example

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function timeout(ms) {
  return new Promise((resolve, reject) => {
    setTimeout(resolve, ms, 'done');
  });
}

timeout(100).then((value) => {
  console.log(value);
});

函数参数的默认值

在ES6之前，不能直接为函数的参数指定默认值，只能采用变通的方法。

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function log(x, y) {
  y = y || 'World';
  console.log(x, y);
}

log('Hello') // Hello World
log('Hello', 'China') // Hello China
log('Hello', '') // Hello World