A.7. “error”语法 =================== “error”元素在[4.1.2.1](../Section04/4.1.2.1.md)、[4.2.2.1](../Section04/4.2.2.1.md)、[5.2](../Section05/5.2.md)、[7.2](../Section07/7.2.md)和[8.5](../Section08/8.5.md)中定义： error = 1*NQSCHAR