# File lib/guard/watcher.rb, line 18
    def initialize(pattern, action = nil)
      @pattern, @action = pattern, action
      @@warning_printed ||= false

      # deprecation warning
      if @pattern.is_a?(String) && @pattern =~ /(^(\^))|(>?(\\\.)|(\.\*))|(\(.*\))|(\[.*\])|(\$$)/
        unless @@warning_printed
          ::Guard::UI.info "*"*20 + "\nDEPRECATION WARNING!\n" + "*"*20
          ::Guard::UI.info "You have a string in your Guardfile watch patterns that seem to represent a Regexp.\nGuard matches String with == and Regexp with Regexp#match.\nYou should either use plain String (without Regexp special characters) or real Regexp.\n"
          @@warning_printed = true
        end

        ::Guard::UI.info "\"#{@pattern}\" has been converted to #{ Regexp.new(@pattern).inspect }\n"
        @pattern = Regexp.new(@pattern)
      end
    end