next_current

# File lib/rexml/validation/relaxng.rb, line 449
      def next_current( event )
        # Expand references
        c = 0 ; max = @choices.size
        while c < max
          if @choices[c][0].class == Ref
            expand_ref_in( @choices[c], 0 )
            @choices += @choices[c]
            @choices.delete( @choices[c] )
            max -= 1
          else
            c += 1
          end
        end
        @events = @choices[@choice..-1].find { |evt| evt[0].matches? event }
        @current = 0
        if @events
          # reorder the choices
          old = @choices[@choice]
          idx = @choices.index( @events )
          @choices[@choice] = @events
          @choices[idx] = old
          @choice += 1
        end

        @events = [] unless @events
      end