Ice feature from zinit in Ruby

ice.rb

module Kernel
  def ice(key, value, on: Object)
    if on.instance_methods.include?(key.to_sym)
      prev = on.instance_method(key)
      on.define_method key do
        on.remove_method key
        on.define_method(key, prev)
        return value
      end
    else
      on.define_method key do
        on.remove_method key
        return value
      end
    end
  end
end