code: function() {
      const calced = calc(this._latlngs);
      const model = (this._resultsModel = L.extend(
        {},
        calced,
        this._getMeasurementDisplayStrings(calced),
        {
          pointCount: this._latlngs.length
        }
      ));
      this.$results.innerHTML = resultsTemplateCompiled({ model });
    }
docs: update results area of dom with calced measure from `this._latlngs`