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Ruby: Different ways to declare a method on a class


class User < ActiveRecord::Base
    def something
      # ....
    end

    def User.something

    end

    def self.something

    end
end

here the first one is an instance method , which can be called only with instance of User

ex: User.new.something

the other two methods are class methods(also called singleton methods). Which can be called only on User class.

ex: User.something

there is also one more way to call class methods

 class User < ActiveRecord::Base
   class << self
     def something
       "wolf"
     end
   end
 end

Categories : Ruby On Rails

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