tagsearch.js

    this.tagSearcher = {
        // Assuming that the user is only appending to the text, search up to X words back
        // for permutations that match a hash key on TagList
        lookup: function() {
            var lastThree = this.text.split(this.whiteSpaceRegexp).reverse().splice(2);
            var phrase = "";
            $.each(lastThree, function(index, word) {
              phrase = word + phrase;
              if(TagList.get(phrase) !== null) {
                return phrase;
              }
              phrase = " " + phrase;
            }
            return null;
        }
    }