Welcome to a post where I look Under the Hood of Ruby! One of the beauties of Ruby is its elegance. When you find yourself writing multiple or repetitive lines of code, Ruby often has a pre-existing method that encapsulates your intent. In this post, my goal is to walk-through what is going on Under the Hood of helpful Ruby syntax.
Let’s put the spotlight on attr_accessor, which efficiently creates attribute setter and getter methods.
In object-oriented programming (OOP), it is common to create a Class and instances of that Class with attributes. For example, if we had a Dog class, we might make multiple instances (e.g., Beethoven is a Dog, Snoopy is a Dog) each with its own attributes (e.g., Beethoven has a name, Snoopy has a name). The Class attributes can be created in Ruby using “setter” and “getter” methods, as follows:
def name=(name)
@name = name
end #<= our setter, setting name to Snoopy
def name
@name
end #<= our getter, allowing access to name Snoopy
This is fine if your dog only has a name. But, that’s not realistic! In programming we mirror the real world, and our dogs should have way more attributes – breed, hair-color, gender, etc. This is where attr_accessor comes to the rescue. With simple comma-separated syntax, it provides the setter and getter for the attributes, as follows:
attr_accessor :name, :breed, :hair-color, :gender
#^=encapsulates setter and getter