code: function(list) {
  
                  if (Array.isArray(list)) {
  
                      this.a.push.apply(this.a, list);
  
                  } else {
  
                      for (var __$0 = (list)[Symbol.iterator](), __$1; __$1 = __$0.next(), !__$1.done;)
                          { var item$0 = __$1.value; this.a.push(item$0); }
                  }
  
                  return this;
              }
docs: Add the contents of iterables