More Understanding

What I Did

1. I spent more time understanding Rails/CK integration and continued cranking out integration tests for “These Numbers Matter”.

   What I Learned

2. attr_accessor :name really just does the following:

   def name
     @name
   end
   def name=(str)
     @name = str
   end
   

   attr_accessor is accessible throughout an object’s life cycle. When an object is saved using any of ActiveRecord’s methods (save, update, etc.) all attributes of your Model other than attr_accessor are saved in the database.

3. Every time you call a method on an object, all you’re really doing is “sending” that object a “message” where the message is the name of the method you called. In this way, the send method allows you to send a message (or call a method) on an object when you don’t know the name of the method until runtime. This is most applicable to instances in which meta programming is involved.
4. Here’s a review on presence calls in RoR:
   • nil? can be used on any object
   • empty? can only be used on arrays, Hashes, String, and the like (it returns true if the object has no value at all)
   • blank? is a Rails implementation allowing for the combination of both nil? and empty?
   • present? is the negation of blank.
5. It’s important to remember that Rspec is simply a DSL written in Ruby targeted at testing.
6. A UID (unique identifier) is a numeric or alphanumeric string that is associated with a single entity within a given system.