> For the complete documentation index, see [llms.txt](https://yar999.gitbook.io/gopl-zh/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://yar999.gitbook.io/gopl-zh/ch5.md).

# 函数

函数可以让我们将一个语句序列打包为一个单元，然后可以从程序中其它地方多次调用。函数的机制可以让我们将一个大的工作分解为小的任务，这样的小任务可以让不同程序员在不同时间、不同地方独立完成。一个函数同时对用户隐藏了其实现细节。由于这些因素，对于任何编程语言来说，函数都是一个至关重要的部分。

我们已经见过许多函数了。现在，让我们多花一点时间来彻底地讨论函数特性。本章的运行示例是一个网络蜘蛛，也就是web搜索引擎中负责抓取网页部分的组件，它们根据抓取网页中的链接继续抓取链接指向的页面。一个网络蜘蛛的例子给我们足够的机会去探索递归函数、匿名函数、错误处理和函数其它的很多特性。


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