code: function(popup, exclusive) {
  
          if (exclusive) {
              //remove all other popups from screen
              for (var i = this.popups.length - 1; i >= 0; --i) {
                  this.removePopup(this.popups[i]);
              }
          }
  
          popup.map = this;
          this.popups.push(popup);
          var popupDiv = popup.draw();
          if (popupDiv) {
              popupDiv.style.zIndex = this.Z_INDEX_BASE['Popup'] +
                                      this.popups.length;
              this.layerContainerDiv.appendChild(popupDiv);
          }
      }
docs: ***************************************************** /* /*                  Popup Functions /* /*     The following functions deal with adding and /*        removing Popups to and from the Map /* ***************************************************** 
  APIMethod: addPopup
  
  Parameters:
  popup - {<OpenLayers.Popup>}
  exclusive - {Boolean} If true, closes all other popups first