Ruby - remove inherited methods

Question

Is it possible to remove some of the inherited methods in Ruby? I mean, I can override it, but is there any other way?

Class ABC
end

a = ABC.new

puts a.id

Here, the method id is inherited from Object along with other methods like tap,class,type etc. I want to remove such methods.

Edit: I'm using Ruby 1.8.7

Answer 1

Yes - undef_method :foo will prevent any calls to the method foo (contrasted with remove_method :foo, which removes the method from the child, but still passes through up the inheritance chain).

Once again, though, why do you want to remove things like id?

Answer 2

You can always create a blank slate class to derive from:

class BlankSlate
  instance_methods.each do |m|
    undef_method(m) unless (m.match(/^__/))
  end
end

This should strip out all methods except for the internal ones that you're not supposed to mess with, like __send__.

Answer 3

As tadman said you can make a BlankSlate object, or in ruby 1.9, there is the BasicObject class that has a bare minimum of methods. A quick google search turned up this for further reading: http://www.humbug.in/docs/ruby-best-practices/I_sect13_d1e2654.html

It appears that Rails already has BlankSlate built in: http://rubydoc.info/docs/rails/2.3.8/BlankSlate