불변성 & 순수함수

import React, { useState } from "react";

function App() {
const [obj, setObj] = useState({
name: "wonjang",
age: 21,
});
return (

<div>
  <div>{obj.name}</div>
  <button
    onClick={() => {
      obj.name = "twojang";
      const obj2 = { ...obj };
      setObj(obj2);
    }}
  >
    변경
  </button>
</div>

);
}

export default App;

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