Book Image

The Ruby Workshop

By : Akshat Paul, Peter Philips, Dániel Szabó, Cheyne Wallace
Book Image

The Ruby Workshop

By: Akshat Paul, Peter Philips, Dániel Szabó, Cheyne Wallace

Overview of this book

The beauty of Ruby is its readability and expressiveness. Ruby hides away a lot of the complexity of programming, allowing you to work quickly and 'do more' with fewer lines of code. This makes it a great programming language for beginners, but learning any new skill can still be a daunting task. If you want to learn to code using Ruby, but don't know where to start, The Ruby Workshop will help you cut through the noise and make sense of this fun, flexible language. You'll start by writing and running simple code snippets and Ruby source code files. After learning about strings, numbers, and booleans, you'll see how to store collections of objects with arrays and hashes. You'll then learn how to control the flow of a Ruby program using boolean logic. The book then delves into OOP and explains inheritance, encapsulation, and polymorphism. Gradually, you'll build your knowledge of advanced concepts by learning how to interact with external APIs, before finally exploring the most popular Ruby framework ? Ruby on Rails ? and using it for web development. Throughout this book, you'll work on a series of realistic projects, including simple games, a voting application, and an online blog. By the end of this Ruby book, you'll have the knowledge, skills and confidence to creatively tackle your own ambitious projects with Ruby.
Table of Contents (14 chapters)

9. Ruby Beyond the Basics I

Activity 9.01: Invoice Generator

Solution

  1. Create a new Ruby file.
  2. Define the invoice_generator method and the p1 and p2 variables to be used in the program using &block and block_given?. We call the invoice_generator method and pass the product prices along with a block of code:
    def invoice_generator(p1,p2, &block)
        yield calc_discount(p1,p2) if block_given?
    end

    The invoice_generator method has a yield keyword, which will only execute the block of code and pass the product prices if the first block of code is passed.

    First, calc_discount is called and then a block code is executed, which, in turn, passes the customer details to the details method.

  3. Next, we will define the discount calculator method, calc_discount, which will calculate the discount on the products, add it to the product, and print the final price of the product. calc_discount is the method where we calculate the sum of the product prices and...