code: function(array, callback, now) {
        var context = this;
        var coll = function() {
          if (_isFunction(array)) {
            callback = array;
            array = this.content;
          }
          var contents = [], doms = false;
          $.each(array, function(i, item) {
            var returned = callback.apply(context, [i, item]);
            if (returned.jquery && returned.length == 1) {
              returned = returned[0];
              doms = true;
            }
            contents.push(returned);
            return returned;
          });
          return doms ? contents : contents.join('');
        };
        return now ? coll() : this.then(coll);
      }
docs: itterates over an array, applying the callback for each item item. the callback takes the same style of arguments as `jQuery.each()` (index, item). The return value of each callback is collected as a single string and stored as `content` to be used in the next iteration of the `RenderContext`.