Science Knowings: JavaScript Course For Social Media

Modules (import-export)

Modules: Breaking Down the Basics

Welcome to the exciting world of Modules! In this session, we'll dive into the fundamentals of modules:

What is a Module?

A module is a self-contained block of code that can be imported and reused in different parts of your application. It helps organize code, prevent conflicts, and promote code reusability.

Importing Modules

To import modules, use the import statement followed by the module's path in your code. This allows you to access the module's exported members.

Exporting Modules

To make a module's members accessible to other modules, you need to export them using the export keyword. This allows you to share code and collaborate efficiently.

Exporting Multiple Named Exports

Exporting multiple named exports allows you to specify specific members to be made available to other modules. This gives you granular control over the exported elements.

Exporting Default Exports (Default Member Exports)

Default exports are a simplified way to export a single member from a module. This member can be imported using the default import syntax in other modules.

Module Resolution

Module resolution is the process of finding the correct module file based on its given identifier (path). It involves searching for the module in various directories and applying specific rules to locate the actual module file.

Module Bundling

Module bundling is the process of combining multiple modules into a single file. This reduces the number of HTTP requests and improves the performance of your web application.

CSS Modules

CSS Modules allow you to encapsulate styles within modules. This helps prevent style conflicts and promotes code reusability.

Module Loading

Module loading is the process of fetching and executing modules. It involves downloading the module files, parsing them, and making the module's exports available to the importing module.

Module Formats

Modules can come in different formats, such as CommonJS, AMD, or UMD. Each format has its own unique syntax and way of defining and exporting modules.

Module Scopes

Module scopes determine the accessibility of variables and functions within a module. Each module has its own private scope, but it can access variables and functions from other modules that are imported.

Dynamic Module Loading

Dynamic module loading allows you to load modules on the fly during runtime. This is useful for implementing lazy loading and other advanced scenarios.

CommonJS Modules

CommonJS modules are popular in Node.js. They use the require() function to import modules and the module.exports object to export module members.

ECMAScript Modules

ECMAScript modules are the native module system in JavaScript. They use the import and export keywords to define and export module members.

Default Parameters

Default parameters allow you to set default values for function parameters. This improves code readability, reduces the need for conditional checks, and enhances code flexibility.