pivotal/projectmonitor

function autocomplete(selector, item_list) {
  $(function() {
    function split( val ) {
      return val.split( /,\s*/ );
    }
    function extractLast( term ) {
      return split( term ).pop();
    }

    $( selector )
      .bind( "keydown", function( event ) {
        if ( event.keyCode === $.ui.keyCode.TAB &&
          $( this ).data( "autocomplete" ).menu.active ) {
          event.preventDefault();
        }
      })
      .autocomplete({
        minLength: 0,
        source: function( request, response ) {
          response( $.ui.autocomplete.filter(
            item_list, extractLast( request.term ) ) );
        },
        focus: function() {
          return false;
        },
        select: function( event, ui ) {
          var terms = split( this.value );
          terms.pop();
          terms.push( ui.item.value );
          this.value = terms.join( ", " ) + ", ";
          return false;
        }
      });
  });
}