/ruby-enumerable-comparable

Primary LanguageRubyOtherNOASSERTION

General Assembly Logo

Ruby Enumerable and Comparable

Prerequisites

Objectives

By the end of this talk, developers should be able to:

  • Add Comparable operators to a class.
  • Add Enumerable methods to a class.

Preparation

  1. Fork and clone this repository. FAQ
  2. Create a new branch, training, for your work.
  3. Checkout to the training branch.
  4. Install dependencies with bundle install.

Introduction

We'll explore an important Ruby mechanism for adding behavior to a class: mixins.

The Comparable Module

Lab - comparing cards

How do you compare cards?

In your squads create an algorithm to determine which of two cards, if either, is "greater" than the other.

Demo

The Comparable module provide common operators to a class that implements the <=> (spaceship) operator. Let's look at lib/card.rb.

Adding the spaceship operator to Card.

Lab - A list as a deck of cards

Let's simulate Enumerable methods using a deck of cards. In your squad, one of you will act as the method and another as the block. The third squad member will record the result.

Cards in Ruby

Let's explore the start of writing a card game in Ruby using lib/card.rb and lib/deck.rb.

The Enumerable Module

We'll build our own list using Ruby's Enumerable module.

Code along - Stepped Range

We'll build a new range class that increments by a provided value. The key to creating an Enumerable class is a correct implementation of the each method.

Tasks

Developers should run these often!

  • bin/rake nag (or bundle exec rake nag): runs code quality analysis tools on your code and complains.
  • bin/rake test (or bundle exec rake test): runs automated tests.

Additional Resources

License

  1. All content is licensed under a CC­BY­NC­SA 4.0 license.
  2. All software code is licensed under GNU GPLv3. For commercial use or alternative licensing, please contact legal@ga.co.