code: function (ruler) {
  			var rulers = this._rulers;
  			for (var i=0; i<rulers.length; i++) {
  				if (rulers[i] === ruler) {
  					rulers.splice(i, 1);
  					ruler.setView(null);
  					this._destroyRuler(ruler);
  					this._update();
  					break;
  				}
  			}
  		}
docs: Removes a ruler from the text view.
  
  @param {orion.editor.Ruler} ruler the ruler.