JavaScript Functions Basics

Introduction

In this lab, we will explore the concept of functions in JavaScript. We will learn how to define and call functions, pass arguments, and return values. Additionally, we will practice using the isFunction() function to check if a given value is a function. By the end of this lab, you will have a solid understanding of how functions work in JavaScript and how to use them effectively in your code.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL javascript(("`JavaScript`")) -.-> javascript/BasicConceptsGroup(["`Basic Concepts`"]) javascript/BasicConceptsGroup -.-> javascript/variables("`Variables`") javascript/BasicConceptsGroup -.-> javascript/data_types("`Data Types`") javascript/BasicConceptsGroup -.-> javascript/arith_ops("`Arithmetic Operators`") javascript/BasicConceptsGroup -.-> javascript/comp_ops("`Comparison Operators`") subgraph Lab Skills javascript/variables -.-> lab-28420{{"`Value Is Function`"}} javascript/data_types -.-> lab-28420{{"`Value Is Function`"}} javascript/arith_ops -.-> lab-28420{{"`Value Is Function`"}} javascript/comp_ops -.-> lab-28420{{"`Value Is Function`"}} end

Checking if a Value is a Function

To check if a value is a function, you can use the typeof operator with the function primitive.

Here's an example of a function that checks if a given value is a function:

const isFunction = (val) => typeof val === "function";

You can use it like this:

isFunction("x"); // false
isFunction((x) => x); // true

To start practicing coding, open the Terminal/SSH and type node.

Summary

Congratulations! You have completed the Value Is Function lab. You can practice more labs in LabEx to improve your skills.

Value Is Function

Introduction

Skills Graph

Checking if a Value is a Function

Summary

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