ReactとMap関数(いくつかの重要な属性に戸惑う)

const numbers = [0, 1, 2, 3, 4];

let newNumbers = [];

for (let i = 0; i < numbers.length; i++) {
	newNumbers.push(numbers[i] * 10);
}

//위의 for loop와 밑의 map function의 결과값은 같다!! map의 위대함이랑 ㅠㅠ

numbers.map((num) => {
  return num * 10;
})

numbers;

numbers.map(num => num * 10);

import React from 'react';

const users = [
  { id: 1, name: 'Leanne Graham' },
  { id: 2, name: 'Ervin Howell' },
  { id: 3, name: 'Clementine Bauch' },
  { id: 4, name: 'Patricia Lebsack' }
];


export default class App extends React.Component {
  render() {
	const renderedUsers = users.map(({ id, name }) => {
    	return <li key={id}>{name}</li>;
    });    
    
    return (
        <ul>
      	  {renderedUsers}
      	</ul>
    );
  }
}

// 결과값

▪ Leanne Graham
▪ Ervin Howell
▪ Clementine Bauch
▪ Patricia Lebsack

const ImageList = props => {
  const images = props.images.map ((image) => {
    return <ImageCard key={image.id} image={image} />;
  });
  
  return <div className="image-list">{images}</div>
};