whole_func_string: function len(head) {
  
  			var length = 0;
  
  			while (head !== null) {
  
  				++length;
  				head = head.next;
  			}
  
  			return length;
  		}
func_code_string: function len(head) {
  
  			var length = 0;
  
  			while (head !== null) {
  
  				++length;
  				head = head.next;
  			}
  
  			return length;
  		}
func_documentation_string: /* js/src/utils/len.js