# File lib/apipie/param_description.rb, line 210
    def concern_subst(string)
      return string if string.nil? or !from_concern?

      original = string
      string = ":#{original}" if original.is_a? Symbol

      replaced = method_description.resource.controller._apipie_perform_concern_subst(string)

      return original if replaced == string
      return replaced.to_sym if original.is_a? Symbol
      return replaced
    end