> For the complete documentation index, see [llms.txt](https://ahnheejong.gitbook.io/ts-for-jsdev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ahnheejong.gitbook.io/ts-for-jsdev/02-ecmascript/block-level-scope/scope-best-practice.md).

# 2.2.3 스코프 베스트 프랙티스

타입스크립트 코드와 같이 let / const가 사용 가능한 환경에서는 항상 var 대신 let 또는 const를 사용하는 것이 좋다. 특히 둘 중에선 **const를 기본적으로 쓰고, 재할당이 반드시 필요한 변수만** **let을 이용해 선언하라**. 이런 코딩 습관은 코드를 읽는 이들이 특정 변수의 값이 블록 내에서 유지될 것이라 짐작하고 잠재적인 실수를 찾아내는 일을 돕는다.


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