// Deserializes a list serialized with serialize_string_list.
function deserialize_string_list(s) {
   var fields = s.split("|")

   var i;
   for (i=0; i<fields.length; i++) {
      if (fields[i] == "^0") {
         fields[i] = null;
      } else {
         var re;

         re = /\^2/g;
         fields[i] = fields[i].replace(re, "|");
   
         re = /\^1/g;
         fields[i] = fields[i].replace(re, "^");
      }
   }

   return fields;
}

function do_populate_cb(s) {
    var array = deserialize_string_list(s);
    var i;
    for (i=0; i<array.length; i++) {
       ... do something with array[i]...
    }
}