def explore_array(method_name)
  code = "[1,2,3,4].#{method_name}"
  puts "Evaluating: #{code}"
  eval code
end

#

orga_input = "find_index(2)"
p explore_array(orga_input) # => 1

otis_input = "map!(&:next)"
p explore_array(otis_input) # => [2, 3, 4, 5]

sunkai_input = "object_id; Dir.glob('*')"
p explore_array(sunkai_input) # => Some sensitive information!!!