Instance methods in Ruby - Mini Project: Build & Apply

Instance methods

📖 Scenario: You are creating a simple program to manage a book's information. You want to store the book's title and author, and then display this information using a method inside the book object.

🎯 Goal: Build a Ruby class called Book that stores a book's title and author. Then, create an instance method description that returns a string describing the book.

📋 What You'll Learn

Create a class named Book with an initialize method that takes title and author as parameters.

Store title and author as instance variables.

Define an instance method called description that returns a string in the format: "Title: [title], Author: [author]".

Create an instance of Book with the title "The Ruby Way" and author "Hal Fulton".

Call the description method on the instance and print the result.

💡 Why This Matters

🌍 Real World

Classes and instance methods are used to model real-world objects in programs, like books, users, or products, making code organized and reusable.

💼 Career

Understanding instance methods is essential for Ruby developers building applications, as it helps create clear and maintainable code with object-oriented design.

1

Create the Book class with initialize method

Create a class called Book with an initialize method that takes two parameters: title and author. Inside initialize, assign @title to title and @author to author.

Ruby

# Define the Book class with initialize method
# Your code here

Need a hint?

Remember, initialize is the method that runs when you create a new object. Use @ to create instance variables.

2

Add the description instance method

Inside the Book class, add an instance method called description that returns a string formatted as: "Title: [title], Author: [author]" using the instance variables @title and @author.

Ruby

class Book
  def initialize(title, author)
    @title = title
    @author = author
  end

  # Define the description method
  # Your code here
end

Need a hint?

Use string interpolation with #{} to include instance variables inside the string.

3

Create a Book instance

Create a variable called my_book and assign it a new instance of Book with the title "The Ruby Way" and author "Hal Fulton".

Ruby

class Book
  def initialize(title, author)
    @title = title
    @author = author
  end

  def description
    "Title: #{@title}, Author: #{@author}"
  end
end

# Create an instance of Book called my_book
# Your code here

Need a hint?

Use Book.new with the exact title and author strings to create the instance.

4

Print the book description

Call the description method on my_book and print the result using puts.

Ruby

class Book
  def initialize(title, author)
    @title = title
    @author = author
  end

  def description
    "Title: #{@title}, Author: #{@author}"
  end
end

my_book = Book.new("The Ruby Way", "Hal Fulton")

# Print the description of my_book
# Your code here

Need a hint?

Use puts my_book.description to print the description string.