bootstrap typeahead multiple selection

bootstrap typeahead multiple selection

function extractor(query) {
        var result = /([^,]+)$/.exec(query);
	if(result && result[1])
	return result[1].trim();
	return '';
}

var subjects = <%= raw autohash.to_json %>;  
$('#search').typeahead({
    source: subjects,
    updater: function(item) {
        return this.$element.val().replace(/[^,]*$/,'')+item+',';
    },
    matcher: function (item) {
      var tquery = extractor(this.query);
      if(!tquery) return false;
      return ~item.toLowerCase().indexOf(tquery.toLowerCase())
    },
    highlighter: function (item) {
      var query = extractor(this.query).replace(/[\-\[\]{}()*+?.,\\\^$|#\s]/g, '\\$&')
      return item.replace(new RegExp('(' + query + ')', 'ig'), function ($1, match) {
        return '<strong>' + match + '</strong>'
      })
    }
});