js中冒号的作用

myLabel:  // 代码块

result = condition ? trueValue : falseValue;

const myObject = {  name: "John",  age: 30};

const { name, age } = myObject;

const [first, second, ...rest] = myArray;

function greet(name = "World") {  console.log(`Hello, ${name}!`);}

switch (value) {  case 1:    // 代码    break;  case 2:    // 代码    break;}