April 2016
Beginner to intermediate
389 pages
9h 8m
Korean
Content preview from 한 권으로 끝내는 Node & Express: 웹사이트 구축을 위한 서버 사이드 자바스크립트
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
333
20
장
-
디버그
20.2.
REPL
과 콘솔을 활용하십시오
노드와 브라우저에는 모두 읽고 평가하고 출력하는 루프
read eval print
loop
(
REPL
)가 존재합니
다. 사실 이는 자바스크립트를 대화형으로 작성하는 기본적인 방법입니다. 자바스크립트는 코
드를 조금 입력하고 엔터를 누르면 즉시 결과를 볼 수 있습니다.
REPL
은 충분히 활용할 만한
훌륭한 방법이며, 작은 코드에서 에러를 찾아내는 가장 빠르고 직관적인 방법이기도 합니다.
브라우저에서는 자바스크립트 콘솔이 곧
REPL
입니다. 노드에서는 아무 옵션 없이
node
라고
입력하면
REPL
모드에 들어갑니다. 여기서 패키지를 불러올(
require
) 수도 있고, 변수나 함
수를 만드는 등, 패키지를 만드는 것만 제외하고 일반적으로 코드에서 할 수 있는 일은 다 할
수 있습니다.
콘솔 로그도 믿음직한 친구입니다. 콘솔 로그는 좀 거친 방법일 수 있지만, 그만큼 이해하기도
쉽고 실행하기도 쉬운 방법입니다. 노드에서
console
.
log
를 호출하면 객체를 읽기 쉬운 형식
으로 보여주므로 쉽게 문제를 찾을 수 있습니다. 물론 일부 객체는 너무 커서 콘솔에 출력해도
유용한 정보를 찾는 데 시간이 너무 많이 걸릴 수 있습니다. 예를 들어 경로 핸들러 아무 것이
든
console
.
log
(
req
)
를 넣어보십시
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.