export

export { name1, name2, , nameN };
export { variable1 as name1, variable2 as name2, , nameN };
//  var, const 
export let name1, name2, , nameN;
export let name1 = , name2 = , , nameN;

//  function  class, function* 
export default expression;
export default function () {  }
export default function name1() {  }

export { name1 as default,  };
export * from ;
export { name1, name2, , nameN } from ;
export { import1 as name1, import2 as name2, , nameN } from ;

nameN

import

export named default named exports, default export export

• Named exports:

  js

  // 
  export { myFunction };
  
  // 
  export const foo = Math.sqrt(2);
  

• export js :

  js

  export default function () {}
  //  'export default class {}'
  // 
  

Named exports import , .

default export .

export default k = 12; // test.js

import m from './test' //  export default ,  import k

console.log(m);        // will log 12

export * from ;

import mod from "mod";
export default mod;

// module "my-module.js"
function cube(x) {
  return x * x * x;
}
const foo = Math.PI + Math.SQRT2;
var graph = {
  options: {
    color: "white",
    thickness: "2px",
  },
  draw: function () {
    console.log("From graph draw function");
  },
};
export { cube, foo, graph };

//You should use this script in html with the type module ,
//eg ''<script type="module" src="demo.js"></script>",
//open the page in a httpserver,otherwise there will be a CORS policy error.
//script demo.js

import { cube, foo, graph } from "my-module";
graph.options = {
  color: "blue",
  thickness: "3px",
};
graph.draw();
console.log(cube(3)); // 27
console.log(foo); // 4.555806215962888

class fallback

// module "my-module.js"
export default function cube(x) {
  return x * x * x;
}

import

import cube from "my-module";
console.log(cube(3)); // 27

Note var, let , const

• import
• ES6 in Depth: Modules, Hacks blog post by Jason Orendorff
• Axel Rauschmayer's book: "Exploring JS: Modules"