The program needs to check and see if the current node is the NULL list.
程序需要检查确认当前节点是否为NULL列表。
You know you're at the end of a list when you hit the null list, written as .
当遇到一个空列表(写为)时，您就会知道已经到了列表的末尾。
If you are just starting a list, then you will use the null list. For example.
如果只是要开始创建列表，那么您必须使用空列表。
Scheme defines a list as being either the null list or a pair whose bottom half is a list.
Scheme将一个列表定义为一个空列表，或者是一个下半部分为某个列表的pair。
The single quotation mark in front of the null list is used to tell Scheme that you are using as data and not as a part of your parse tree.
空列表前面的单引号用来告诉scheme您正在使用作为数据，而不是用它作为解析树的一部分。
Notice how like our recursive programs, the definition of a linked list also contains a base case -- in this case, the NULL pointer.
注意，与我们的递归程序非常类似，链表的定义也包括一个基线条件 ——在这里是NULL指针。
Since a NULL pointer terminates a list, we can also use the NULL pointer condition as a base case for many of our recursive functions on linked lists.
由于NULL指针会结束一个链表，所以我们也可以使用 NULL 指针条件作为基于链表的很多递归程序的基线条件。
For simplicity, we chose not to validate entries into the list by returning a value of null each time the validator is run.
为简单起见，我们选择不验证列表中的条目，每次运行检验器时返回空值。
A linked list consists of a node structure that contains two members: the data it is holding and a pointer to another node structure (or NULL, to terminate the list).
链表所包含的节点结构体由两部分构成：它所持有的数据，以及指向另一个节点结构体(或者是NULL，结束链表)的指针。
The last example, (), is used to refer to the empty, or null, list.
最后一个示例 ()用来表示一个空列表。
I said earlier that an empty list is a LinkedList containing a null pointer in both fields.
我前面说过，空链表就是两个域都包含一个空指针的LinkedList。
If the method returns null, it means this is the first time through, so the servlet needs to retrieve the list from the database.
如果方法返回空，意味着这是第一次访问，所以servlet需要从数据库检索列表。
If the list is null, require will throw an exception.
如果这个列表是null,require会抛出一个异常。
We also alluded to the fact that find could produce a list of file names with null delimiters, and that is what the -print0 option does.
我们还提到find可以生成一个以null分隔符分隔的文件名列表，这是-print 0选项所起的作用。
In lines 22 through 34 you select an operating system that is not NULL from the list obtained in previous step.
从第22行到第34行从上一步中获得的数组中选择一个不为空的操作系统。
Notice how like our recursive programs, the definition of a linked list also contains a base case — in this case, the NULL pointer.
注意，与我们的递归程序非常类似，链表的定义也包括一个基线条件——在这里是NULL指针。
If a list is found that corresponds to the input word, the list is returned to the client, otherwise a null is returned.
如果发现与输入单词相对应的列表，那么该列表将被返回给客户机，否则将返回null。
After executing the query against the database, return the results of the query as list or null if no synonym is found.
对数据库执行查询后，以列表形式返回查询结果，如果没有找到同义词的话则返回null。
The second filter removes any list items where the left side of the expression is a primitive type or a null.
第二个过滤器负责移除任何表达式左侧为一个基本类型或null型的列表条目。
Pointer to the image list to which the dragging bitmap was added, if successful; otherwise NULL.
如果成功，则返回指向图像列表的指针，拖动位图将被加入到其中去；否则返回NULL。
A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.
给定一个链表，其中的节点包含一个额外的随机指针，可能指向链表中的任意一个节点或者为空。
Returns a pointer to the last item in the list, or null if the list is empty.
返回指向列表中最后一个项的指针，如果列表为空返回空。
Returns a pointer to the last item in the list, or null if the list is empty.
返回指向列表中最后一个项的指针，如果列表为空返回空。
应用推荐