So today I had an interesting problem. For whatever the reason, I wanted to have a class automagically be created. It was going to be a helper model, and I didn’t feel like having umteen classes that all did the same thing, just had different names for different tables. My solution: use the power of ruby and metaprogramming

def create_new_active_record_model(class_name)
  klass = Class.new(ActiveRecord::Base) do
    belongs_to :old, :class_name => class_name
    def some_method_you_want
      "something"
    end
  end
  Object.const_set "#{class_name}Target", klass
end

I know that some of this could have been encapsulated in a polymorphic association but this allows you to do something beyond just keeping everything in one table, like with polymorphic associations.

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