一行代码就能完成的事情，为什么要写两行

if (age < 18) {
  me = '小姐姐';
} else {
  me = '老阿姨';
}

me = age < 18 ? '小姐姐' : '老阿姨';

const you = "董员外"
const your = "菜鸡本鸡"
const me = you ？"点再看":your？"点赞":"分享"

if(
    type == 1 ||
    type == 2 ||
    type == 3 ||
    type == 4 ||
){
   //...
}

if( [1,2,3,4,5].includes(type) ){
   //...
}

const obj = {
    a:1,
    b:2,
    c:3,
}
//老的取值方式
const a = obj.a;
const b = obj.b;
const c = obj.c;

const {a,b,c} = obj;

if(obj && obj.name){
  const name = obj.name
}

const name = obj?.name;

const reverse = str => str.split('').reverse().join('');
reverse('hello world');   // 'dlrow olleh'

const randomString = () => Math.random().toString(36).slice(2);
//函数调用
randomString();

const unique = (arr) => [...new Set(arr)];
console.log(unique([1, 2, 2, 2, 3, 4, 4, 5, 6, 6]));

const uniqueObj = (arr, fn) =>arr.reduce((acc, v) => {if (!acc.some(x => fn(v, x))) acc.push(v);return acc;}, []);
uniqueObj([{id: 1, name: '大师兄'}, {id: 2, name: '小师妹'}, {id: 1, name: '大师兄'}], (a, b) => a.id == b.id)
// [{id: 1, name: '大师兄'}, {id: 2, name: '小师妹'}]

const a = [1,2,3];
const b = [1,5,6];
const c = [...new Set([...a,...b])];//[1,2,3,5,6]

const notEmpty = arr => Array.isArray(arr) && arr.length > 0;
notEmpty([1, 2, 3]);  // true

//旧写法
let a=1;
let b=2;
let temp;
temp=a
a=b
b=temp
//新写法
[a, b] = [b, a];

const isEven = num => num % 2 === 0;
isEven(996); 

const random = (min, max) => Math.floor(Math.random() * (max - min + 1) + min);
random(1, 50);

const isWeekday = (date) => date.getDay() % 6 !== 0;
console.log(isWeekday(new Date(2021, 11, 11)));
// false 
console.log(isWeekday(new Date(2021, 11, 13)));
// true

const goToTop = () => window.scrollTo(0, 0);
goToTop();

const touchSupported = () => {
  ('ontouchstart' in window || window.DocumentTouch && document instanceof window.DocumentTouch);
}
console.log(touchSupported());

const isAppleDevice = /Mac|iPod|iPhone|iPad/.test(navigator.platform);
console.log(isAppleDevice);
// Result: will return true if user is on an Apple device

const copyToClipboard = (text) => navigator.clipboard.writeText(text);
copyToClipboard("双十一来了~");

const isDarkMode = window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches
console.log(isDarkMode)

filter:grayscale(100%)