Not every tag is a simple symbol in the SXML structure; specifically, a namespace-qualified tag is a pair instead.
SXML结构中,每个标签并非都是简单的符号,特别地,命名空间限定的标签就有两个符号。
2
Figure 3 shows the first example of this type, with the same XML document structure bound to a single class rather than the pair of classes used previously.
图3显示了该类型的第一个示例,它将相同的XML文档结构绑定到单个类,而不是以前使用的两个类。
3
Here's the trick: Instead of containing the empty class as a member, the pairstructure in Boost derives from the empty class.