constantize (ActiveSupport::Inflector)

    # File lib/active_support/inflector.rb, line 346
          def constantize(camel_cased_word)
            names = camel_cased_word.split('::')
            names.shift if names.empty? || names.first.empty?

            constant = Object
            names.each do |name|
              constant = constant.const_defined?(name) ? constant.const_get(name) : constant.const_missing(name)
            end
            constant
          end