# File lib/rouge/lexers/php.rb, line 35
      def builtins
        return [] unless @funcnamehighlighting

        @builtins ||= Set.new.tap do |builtins|
          self.class.builtins.each do |mod, fns|
            next if @disabledmodules.include? mod
            builtins.merge(fns)
          end
        end
      end