> 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/function.md).

# 2.3 함수

자바스크립트의 함수는 일급 객체다. 함수를 다른 함수의 인자로 넘길 수도 있고, 함수가 함수를 리턴하기도 하는 등 함수가 다른 문자열, 숫자 등의 값과 동일하게 취급된다. 때문에 함수는 자바스크립트 프로그래밍에서 가장 핵심적인 역할을 차지한다. 이 장에서는 최신 ECMAScript 명세에서 자바스크립트 함수에 어떤 변경점이 있었는지 알아본다.


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