add: for(var i=0; i < this.layers.length; i++) { if (this.layers[i] == layer) { return false; } }  
context:     addLayer: function (layer) {        layer.div.style.overflow = "";        this.setLayerZIndex(layer, this.layers.length);        if (layer.isFixed) {            this.viewPortDiv.appendChild(layer.div);        } else {            this.layerContainerDiv.appendChild(layer.div);        }        this.layers.push(layer);        layer.setMap(this);        if (layer.isBaseLayer)  {            if (this.baseLayer == null) {                // set the first baselaye we add as the baselayer                this.setBaseLayer(layer);            } else {                layer.setVisibility(false);            }        } else {            if (this.getCenter() != null) {                layer.moveTo(this.getExtent(), true);               }        }        this.events.triggerEvent("addlayer");    },
meta: 8310	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/8310/a779f0e69a2722c649e4794a4aca40cd7471990e/Map.js/clean/lib/OpenLayers/Map.js