how to override [] brackets in ruby?

Question

I am writing an Ajax request form with Ruby on Rails using a collection_select tag that looks like this:

<%= collection_select(\"Jobs\", \"cl         


        

Answer 1

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

Answer 2

@German, tried to get answer for your question.

2.1.3 :025 > class AntiArray < Array
2.1.3 :026?>     def [](ind)
2.1.3 :027?>         self.fetch(-ind) + 1
2.1.3 :028?>     end
2.1.3 :029?>   end
 => :[] 
2.1.3 :030 > y = AntiArray.new([1,2,3,4])
 => [1, 2, 3, 4] 
2.1.3 :031 > y[1]
 => 5 
2.1.3 :032 > 

Hope this is what you are asking for. Given a try for you

Answer 3

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.