> For the complete documentation index, see [llms.txt](https://incheol-jung.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://incheol-jung.gitbook.io/docs/study/nodejs/2018-01-16-nodejs-9st.md).

# 9회차

## 콜백헬 개선

* Promise 

  아래와 같은 callbackhell을 개선하기 위함

```javascript
    asyncfunction(params,function(){
      asyncfunction(params,function(){
           asyncfunction(params,function(){
                 asyncfunction(params,function(){
                 });
           });
      });
});
```

* ES6 Generator

```javascript
    function* iterFunc(){
        yeild console.log("첫번째 출력");
        yeild console.log("두번째 출력");
        yeild console.log("세번째 출력");
        yeild console.log("네번째 출력");
    }

    // yield를 만나면 출력을 하고 멈춘다
    // -> 위와 같이 만든함수를 generator 라고 한다
```

* co module

npm install --save co <https://github.com/tj/co>

* async await 사용법

## 이지윅에디터

### 서머노트 특징

* 국내 개발자가 구현
* 부트스트랩기반
* 파일업로드는 ajax로 직접구현
* 반응형 지원

### 기타 시작 및 api확인

URL : <http://summernote.org/getting-started/>


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