From: Hemant Kumar <gethemant@...>
Date: 2007-01-11T13:30:31+09:00
Subject: Re: statement outside of any method in a class

On Thu, 2007-01-11 at 13:01 +0900, Paul Smith wrote:
> Newbie question:
> 
> In the following code:
> 
>   class Person < ActiveRecord::Base
>      validates_presence_of :first_name
>   end
> 
> validates_presence_of is a method call that is
> specified outside of any method in class Person.
> 

Hmm validates_presence_of method is not "outside any method" in class
Person actually. Most probably (i.e taking into account rails meta
magic), validates_presence_of is a class method, which is defined in
class ActiveRecord::Base.

So, when Person class inherits ActiveRecord::Base class it also inherits
method validates_presence_of and above mentioned line invokes the method
with argument :first_name.

class Foobar
  def self.sayfoo arg
    puts "You said #{arg}"
  end
end

class Baz < Foobar
  sayfoo :rubyrocks
end

Output #=> "You said rubyrocks"


Unlike C++, where you can have class or instance methods of a class(i.e
static or normal methods of class) defined outside class definition, in
Ruby its always inside class.