Cracking the JavaScript Coding Interview: Practice Problems

Explore the difference between a function expression and a function declaration in JavaScript. Practice problems will reinforce this topic within the course.

Compare function declarations and function expressions, noting hoisting differences, anonymous forms, and how declarations load before code while expressions depend on execution order.

Explore hoisting by predicting what gets logged when a function runs and when a text variable is logged, sharpening your JavaScript interview problem-solving skills.

Uncover hoisting and scope in JavaScript by tracing a log function and a redeclared text variable, yielding undefined and foo. See how declarations hoist and how function scope affects values.

Explore what scope means in JavaScript and how it works, addressing your question in this section.

Explore how scope in JavaScript governs variable visibility, differentiating global and local variables, and how functions create new scopes, leading to reference errors or global assignments.

Examine the given code to determine what will be logged when the program is read, focusing on the behavior of const, var, and let.

Explore how var, let, and const differ in scope and reassignment, with block scope versus global scope illustrated and ES6 introducing these keywords.

Analyze how the this keyword affects what gets logged to the console in the shown code. Determine the outputs for the full name at lines 12 and 16.

Explore how the this keyword refers to the object it is inside, and how invocation context can make it point to the global window object or a specific object.

Identify use cases for arrow functions and explain at least one limitation, equipping you to tackle interview questions on JavaScript syntax.

Explore a use case for arrow functions and name a limitation, such as their lack of this binding in object methods and their inability to be used as constructors.

Learn to implement a closure-based counter in JavaScript that tracks how many times a function is invoked, with all logic contained inside the function.

Use closures to create private state in a counter function that tracks how many times it runs, by returning an anonymous function and instantiating it.

Use strict enforces stricter parsing and runtime error handling, making undeclared variables and duplicate parameters throw errors and ensuring this is undefined in global scope, boosting secure, fail-fast code.

Master the IIFE design pattern in JavaScript by explaining what an IIFE is, why it’s useful, and creating a working example yourself.

Learn how immediately invoked function expressions create private scopes to protect data and prevent global pollution, using closures to simulate private variables and keep libraries like jQuery safe.