• Ruby Enumerable Builtins
• Ruby Object

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

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

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.

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

How do you compare cards?

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

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.

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.

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

It's a best practice to keep our exposed API as small as necessary. I like to keep methods private by default (just like data is) by decorating them with the private method. This makes them uncallable outside the class definition. For example:

class Foo
  def bar
    "baz"
  end
  private :bar

  def qux
    bar # this works
  end
end

Foo.new.bar # this does not work

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

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.

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.

• List ADT

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2. All software code is licensed under GNU GPLv3. For commercial use or alternative licensing, please contact [email protected].