Other Structures（其他结构）

While cons cells and lists are typically considered to be synonymous, that’s not quite right—as I mentioned earlier, you can use lists of lists to represent trees. Just as the functions discussed in this chapter allow you to treat structures built out of cons cells as lists, other functions allow you to use cons cells to represent trees, sets, and two kinds of key/value maps. I’ll discuss some of those functions in the next chapter.

尽管点对单元和列表通常被视作同义词，但这并不很准确。正如我早先提到的，你可以使用列表的列表来表示树。正如本章所讨论的函数允许你将构建在点对单元上的结构视为列表那样，其他函数也允许你使用点对单元来表示树、集合以及两类键/值映射表。我将在第 13 章讨论这类函数中的一些。