# File lib/action_view/helpers/java_script_macros_helper.rb, line 106
      def auto_complete_field(field_id, options = {})
        function =  "new Ajax.Autocompleter("
        function << "'#{field_id}', "
        function << "'" + (options[:update] || "#{field_id}_auto_complete") + "', "
        function << "'#{url_for(options[:url])}'"
        
        js_options = {}
        js_options[:tokens] = array_or_string_for_javascript(options[:tokens]) if options[:tokens]
        js_options[:callback]   = "function(element, value) { return #{options[:with]} }" if options[:with]
        js_options[:indicator]  = "'#{options[:indicator]}'" if options[:indicator]
        {:on_show => :onShow, :on_hide => :onHide, :min_chars => :min_chars}.each do |k,v|
          js_options[v] = options[k] if options[k]
        end
        function << (', ' + options_for_javascript(js_options) + ')')

        javascript_tag(function)
      end