Import functions from another js file. Javascript

The following works for me in Firefox and Chrome. In Firefox it even works from file:///

models/course.js

export function Course() {
    this.id = '';
    this.name = '';
};

models/student.js

import { Course } from './course.js';

export function Student() {
    this.firstName = '';
    this.lastName = '';
    this.course = new Course();
};

index.html

<div id="myDiv">
</div>
<script type="module">
    import { Student } from './models/student.js';

    window.onload = function () {
        var x = new Student();
        x.course.id = 1;
        document.getElementById('myDiv').innerHTML = x.course.id;
    }
</script>

You can try as follows:

//------ js/functions.js ------
export function square(x) {
    return x * x;
}
export function diag(x, y) {
    return sqrt(square(x) + square(y));
}

//------ js/main.js ------
import { square, diag } from './functions.js';
console.log(square(11)); // 121
console.log(diag(4, 3)); // 5

You can also import completely:

//------ js/main.js ------
import * as lib from './functions.js';
console.log(lib.square(11)); // 121
console.log(lib.diag(4, 3)); // 5

Normally we use ./fileName.js for importing own js file/module and fileName.js is used for importing package/library module

When you will include the main.js file to your webpage you must set the type="module" attribute as follows:

<script type="module" src="js/main.js"></script>

For more details please check ES6 modules