JavaScript Modules & ImportExport - Practice Questions 2026
Course Description
Master the art of modular JavaScript with this comprehensive practice exam course. Whether you are preparing for technical interviews or building scalable web applications, understanding how to structure code using ES6 Modules is a fundamental skill for every modern developer.
Why Serious Learners Choose These Practice Exams
This course is designed for developers who want to move beyond surface-level tutorials. Serious learners choose these exams because they provide a rigorous environment to test knowledge of scope, execution order, and memory management within JavaScript modules. Instead of simple syntax checks, our questions challenge your ability to debug complex dependency trees and understand the nuances of the import and export statements in real-world environments.
Course Structure
This course is organized into six logical levels to ensure a smooth learning curve:
Basics / Foundations: We begin with the fundamental "why" behind modules. This section covers the transition from script tags to modules, the type="module" attribute in HTML, and the basic syntax of named exports.
Core Concepts: Here, we dive into the mechanics of default exports, the difference between named and default imports, and how to use the as keyword for aliasing to prevent naming conflicts.
Intermediate Concepts: This level explores module objects and the import * syntax. You will learn how modules behave as singletons and how to re-export modules from a central entry point.
Advanced Concepts: We tackle complex topics such as dynamic imports using import(), top-level await, and the intricacies of live bindings where exported values remain connected to their source.
Real-world Scenarios: These questions simulate architectural decisions, such as choosing between CommonJS and ES Modules (ESM) or handling circular dependencies in large-scale applications.
Mixed Revision / Final Test: A comprehensive capstone exam that pulls questions from all previous levels to ensure you have a holistic command of the subject matter.
Sample Practice Questions
QUESTION 1
In a JavaScript module, what happens if you attempt to re-assign a value to a variable that has been imported using a named import?
OPTION 1: The value is updated in both the current and the source module.
OPTION 2: The value is updated only in the current module.
OPTION 3: It throws a TypeError: Assignment to constant variable.
OPTION 4: It results in a SyntaxError during the parsing phase.
OPTION 5: The assignment is ignored and the code continues to execute.
CORRECT ANSWER: OPTION 3
CORRECT ANSWER EXPLANATION: Imports in JavaScript are "read-only live bindings." While the value in the source module can change and the import will reflect that change, the importing module cannot re-assign the identifier. Attempting to do so results in a runtime TypeError.
WRONG ANSWERS EXPLANATION:
OPTION 1: JavaScript modules do not allow two-way data binding through imports.
OPTION 2: Named imports are not local copies; they are bindings to the exported value.
OPTION 4: This is a runtime error (TypeError), not a syntax error, as the syntax itself is valid but the operation is forbidden.
OPTION 5: JavaScript does not fail silently in this scenario; it stops execution by throwing an error.
QUESTION 2
What is the primary difference between a default export and a named export when importing them?
OPTION 1: Default exports must be imported using curly braces.
OPTION 2: Named exports can be renamed during import without the 'as' keyword.
OPTION 3: There can be multiple default exports per file but only one named export.
OPTION 4: Default exports are imported without curly braces and can be assigned any name.
OPTION 5: Named exports are hoisted while default exports are not.
CORRECT ANSWER: OPTION 4
CORRECT ANSWER EXPLANATION: A module can have only one default export. When importing it, you do not use curly braces, and you can name the import whatever you like. Named exports require curly braces and must match the exported name unless the 'as' keyword is used.
WRONG ANSWERS EXPLANATION:
OPTION 1: This is the opposite of the truth; named exports use curly braces.
OPTION 2: Named exports strictly require the 'as' keyword for renaming.
OPTION 3: The rule is the exact opposite: multiple named exports, one default export.
OPTION 5: Hoisting behavior in modules depends on the declaration (function vs. const), not whether it is a default or named export.
Welcome to the best practice exams to help you prepare for your JavaScript Modules & ImportExport.
You can retake the exams as many times as you want.
This is a huge original question bank.
You get support from instructors if you have questions.
Each question has a detailed explanation.
Mobile-compatible with the Udemy app.
30-days money-back guarantee if you're not satisfied.
We hope that by now you're convinced! And there are a lot more questions inside the course.
Save $19.99 · Limited time offer
Related Free Courses
6 Practice Exams | Project Management Professional (PMP)
6 Practice | PCEP – Certified Entry-Level Python Programmer
6 Practice Exams | Microsoft Certified Azure Fundamentals
