rename layers in illustrator

renamelayers.jsx

#target illustrator
 
var docRef = app.activeDocument;
 
with (docRef) {
    
    var layerlist = new Array();
    
    for (var i = layers.length-1; i >= 0; i--) {
         if (layers[i].visible == true){
             
          
             layerlist.push(layers[i]);
 
               };
          };
      
      for (var key in layerlist){
          
   layerlist[key].name = 'layer name '+ key;          
          }
      
      
      
        };