JavaScript has its share of design errors, such as the overloading of + to mean both addition and concatenation with type coercion, and the error-prone with statement should be avoided.

• JavaScript也有它设计上的错误，比如重载的+号随着类型的不同既表示"相加"又表示"连接"，和本该避免的有错误倾向的with语句。