arrow function ์ ๋ํ ๊ธ์ ์ฒจ๋ถํฉ๋๋ค. Arrow function expressions - JavaScript | MDN An arrow function expression is a compact alternative to a traditional function expression, with some semantic differences and deliberate limitations in usage: developer.mozilla.org ๐ค ๋ฌธ์ ์ํฉ ์๋์ ๊ฐ์ ์ฝ๋๋ฅผ ์คํํ๋ ค๋ ์ ๋๋ก ์๋๋์ง ์์์ต๋๋ค. const setIsActive = (open) => (event) => { setCategoryState(open); }; function onClickLeaf() { setI..