Exercise 2: Destructuring in JavaScript

Make this exercise in Visual Studio Code and node.js.

These exercises practice the destructuring in JavaScript, which will be valuable when you start learning React.

2.1 Basic Array Destructuring

Exercise:

Given the array:

const fruits = ['apple', 'banana', 'cherry'];

Use array destructuring to assign the values to variables firstFruit, secondFruit, and thirdFruit. Print each variable to check the result.

Expected Output:

apple
banana
cherry

2.2 Skipping Elements in Arrays

Exercise:

Given the array:

const colors = ['red', 'green', 'blue', 'yellow'];

Use destructuring to assign the first and third colors to firstColor and thirdColor, skipping the second color.

Expected Output:

red
blue

2.3 Default Values with Array Destructuring

Exercise:

Given an array that might be missing values:

const numbers = [10, 20];

Use destructuring to assign num1, num2, and num3, where num3 should default to 30 if it’s not in the array. Print each variable to check the result.

Expected Output:

num1: 10
num2: 20
num3: 30

2.4 Object Destructuring Basics

Exercise:

Given the object:

const person = { name: 'Alice', age: 25, city: 'Wonderland' };

Use object destructuring to assign the name, age, and city properties to separate variables. Print each variable to check the result.

Expected Output:

Alice
25
Wonderland

2.5 Renaming Variables in Object Destructuring

Exercise:
Given the object:

const book = { title: '1984', author: 'George Orwell', year: 1949 };

Use destructuring to assign title to bookTitle, author to bookAuthor, and year to publicationYear. Print each variable.

Expected Output:

bookTitle: 1984
bookAuthor: George Orwell
publicationYear: 1949

2.6 Nested Object Destructuring

Exercise:
Given the object:

const student = {
  name: 'Bob',
  grade: 10,
  subjects: {
    math: 'A',
    science: 'B'
  }
};

Use nested destructuring to get name, grade, and the math grade. Print each variable.

Expected Output:

Bob
10
A

2.7. Function Parameter Destructuring

Exercise:

Define a function displayPerson that takes an object as a parameter with properties name, age, and city. Use destructuring in the function’s parameter to access these properties directly. Call the function with:

displayPerson({ name: 'Charlie', age: 30, city: 'Paris' });

Expected Output:

Name: Charlie, Age: 30, City: Paris

2.8 Swapping Variables Using Array Destructuring

Exercise:

Given two variables:

let a = 5;
let b = 10;

Use array destructuring to swap the values of a and b. Print the variables to check the result.

Expected Output:

a: 10
b: 5

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3. semester efterår 2024