how to override [] brackets in ruby ?

Answer 1

You need to use params[:Jobs][:clearance]

params is a hash of all the request parameters. But params[:Jobs] is ALSO a hash of all :Jobs parameters. So calling params[:Jobs][:clearance] is calling the [] method on the params[:Jobs] object passing :clearance in as a parameter.

Answer 2

kmorris solved your problem (very well) but i would like to answer your question: you can override [] and []= operators because they are methods (like almost everything), but you should think well about what you are doing because you can break tons of things.

class AntiArray < Array

  def [](ind)
    self.fetch(-ind)
  end

end

y = AntiArray.new([1,2,3,4])

y[1]

=> 4