Lambda是一个过程构造函数。你可以在运行时合成程序，尽管Python的lambda不是很强大。请注意，很少有人理解这种编程。

I started reading David Mertz's book today 'Text Processing in Python.' While he has a fairly terse description of Lambda's the examples in the first chapter combined with the explanation in Appendix A made them jump off the page for me (finally) and all of a sudden I understood their value. That is not to say his explanation will work for you and I am still at the discovery stage so I will not attempt to add to these responses other than the following: I am new to Python I am new to OOP Lambdas were a struggle for me Now that I read Mertz, I think I get them and I see them as very useful as I think they allow a cleaner approach to programming.

He reproduces the Zen of Python, one line of which is Simple is better than complex. As a non-OOP programmer reading code with lambdas (and until last week list comprehensions) I have thought-This is simple?. I finally realized today that actually these features make the code much more readable, and understandable than the alternative-which is invariably a loop of some sort. I also realized that like financial statements-Python was not designed for the novice user, rather it is designed for the user that wants to get educated. I can't believe how powerful this language is. When it dawned on me (finally) the purpose and value of lambdas I wanted to rip up about 30 programs and start over putting in lambdas where appropriate.

只是函数的一种奇特说法。除了它的名字，它没有什么晦涩、吓人或神秘的地方。当你读到下面这行，在脑海中用函数替换lambda:

>>> f = lambda x: x + 1
>>> f(3)
4

它只是定义了一个关于x的函数。其他一些语言，比如R，显式地说:

> f = function(x) { x + 1 }
> f(3)
4

你看到了什么?这是编程中最自然的事情之一。

我刚开始学习Python，然后一头栽进Lambda——这花了我一段时间才弄明白。

请注意，这不是对任何事情的谴责。每个人都有不容易得到的东西。

lambda是那些在现实生活中应该被遗忘的“有趣”语言项目之一吗?

No.

我相信有一些边缘情况可能需要它，但考虑到它的模糊性，

它并不晦涩。在我过去工作过的两个团队中，每个人都一直在使用这个功能。

它在未来版本中被重新定义的可能性(我基于它的各种定义的假设)

除了几年前修复闭包语义之外，我还没有看到在Python中重新定义它的严肃建议。

编码清晰度的降低——应该避免吗?

如果你用对了，也不会不太清楚。相反，拥有更多可用的语言结构可以增加清晰度。

这让我想起了C类型的溢出(缓冲区溢出)——指向顶部变量并重载以设置其他字段值……有点像技术人员的表演技巧，但维护程序员的噩梦。

就像缓冲区溢出?哇。如果您认为lambda是一个“维护噩梦”，我无法想象您将如何使用它。

两行总结:

闭包:非常有用。学习它们，利用它们，热爱它们。 Python的lambda关键字:不必要，偶尔有用。如果你发现自己在用它做任何复杂的事情，把它放在一边，定义一个真正的函数。

Lambdas通常与函数式编程风格密切相关。通过将函数应用于某些数据并合并结果来解决问题，这是谷歌用于实现其大多数算法的思想。

以函数式编程风格编写的程序很容易并行化，因此在现代多核机器中变得越来越重要。 所以简而言之，不，你不应该忘记他们。