null pointer

常见例句

NULL is defined simply as a null pointer (0) because the null pointer is invalid as a pointer anyway.
NULL 被簡單地定義爲一個空指針（0），因爲無論如何空指針都不是郃法的指針。
Instead of defining a separate class for empty lists, it represents empty lists by putting a null pointer in both fields.
它在兩個域中都放置一個空指針來表示空鏈表，而不是爲空鏈表定義一個單獨的類。
Unlike, for example, a class-cast exception, a null-pointer exception says nothing about what was expected instead of the null pointer.
例如，不像一個類轉型異常，空指針異常不給出它所需要的內容的任何信息，衹有一個空指針。