how can I write my own validation helper method that can be reused in several different models

I want to write one common validation helper metho开发者_开发问答d that can be used in different models e.g.

def validate_my_own_column(arg1, arg2)
{
  if arg1 > arg2
   ...
  else
   ...
  end
}

I want to call validate_my_own_column(arg1, arg2) method in various models. how can I achieve this?

Thanks

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You tagged this question ruby-on-rails-2. Unfortunately what you want is somewhat complicated to do in Rails 2. If you are in fact using Rails 3, it's simple: take a look at http://api.rubyonrails.org/classes/ActiveModel/Validator.html.