In addition to other answers, one reason Python and most other multi-paradigm languages are not well suited for true functional programming is because their compilers / virtual machines / run-times do not support functional optimization. This sort of optimization is achieved by the compiler understanding mathematical rules. For example, many programming languages support a map function or method. This is a fairly standard function that takes a function as one argument and a iterable as the second argument then applies that function to each element in the iterable.

不管怎样，map(foo()， x) * map(foo()， y)和map(foo()， x * y)是一样的。后者实际上比前者快，因为前者执行两个副本，而后者执行一个副本。

更好的函数式语言能够识别这些基于数学的关系，并自动执行优化。不致力于函数式范式的语言可能无法优化。

我从来不会称Python为“函数式”，但无论何时我用Python编程，代码总是几乎完全是函数式的。

不可否认，这主要是由于非常好的列表理解。所以我不一定建议Python作为函数式编程语言，但我建议使用Python的人进行函数式编程。

Guido对此有很好的解释。以下是最相关的部分:

I have never considered Python to be heavily influenced by functional languages, no matter what people say or think. I was much more familiar with imperative languages such as C and Algol 68 and although I had made functions first-class objects, I didn't view Python as a functional programming language. However, earlier on, it was clear that users wanted to do much more with lists and functions. ... It is also worth noting that even though I didn't envision Python as a functional language, the introduction of closures has been useful in the development of many other advanced programming features. For example, certain aspects of new-style classes, decorators, and other modern features rely upon this capability. Lastly, even though a number of functional programming features have been introduced over the years, Python still lacks certain features found in “real” functional programming languages. For instance, Python does not perform certain kinds of optimizations (e.g., tail recursion). In general, because Python's extremely dynamic nature, it is impossible to do the kind of compile-time optimization known from functional languages like Haskell or ML. And that's fine.

我从中得出两点结论:

该语言的创造者并不真正认为Python是一种函数式语言。因此，可能会看到“函数式”的特性，但不太可能看到任何明确的功能。 Python的动态特性抑制了您在其他函数式语言中看到的一些优化。当然，Lisp和Python一样是动态的(如果不是更动态的话)，所以这只是部分解释。

让我用一段代码来演示，这段代码摘自一个关于SO的“函数式”Python问题的答案

Python:

def grandKids(generation, kidsFunc, val):
  layer = [val]
  for i in xrange(generation):
    layer = itertools.chain.from_iterable(itertools.imap(kidsFunc, layer))
  return layer

Haskell:

grandKids generation kidsFunc val =
  iterate (concatMap kidsFunc) [val] !! generation

这里的主要区别是Haskell的标准库具有用于函数式编程的有用函数:在本例中是iterate、concat和(!!)

您引用的问题是哪些语言同时促进面向对象和函数式编程。Python并不提倡函数式编程，尽管它工作得相当好。

反对Python中函数式编程的最佳论据是Guido仔细考虑了命令式/OO用例，而函数式编程用例则没有。当我编写命令式Python时，它是我所知道的最漂亮的语言之一。当我编写函数式Python时，它变得像没有BDFL的普通语言一样丑陋和令人不快。

这并不是说它不好，只是说您必须比转换到促进函数式编程的语言或转换到编写OO Python时更加努力。

以下是我在Python中遗漏的函数性内容:

模式匹配 尾递归 大型列表函数库 函数式字典类 自动加脂法 简洁的组合函数的方法 懒惰的列表 简单、强大的表达式语法(Python的简单块语法阻止Guido添加它)

No pattern matching and no tail recursion mean your basic algorithms have to be written imperatively. Recursion is ugly and slow in Python. A small list library and no functional dictionaries mean that you have to write a lot of stuff yourself. No syntax for currying or composition means that point-free style is about as full of punctuation as explicitly passing arguments. Iterators instead of lazy lists means that you have to know whether you want efficiency or persistence, and to scatter calls to list around if you want persistence. (Iterators are use-once) Python's simple imperative syntax, along with its simple LL1 parser, mean that a better syntax for if-expressions and lambda-expressions is basically impossible. Guido likes it this way, and I think he's right.

Python几乎是一种函数式语言。它是“功能精简版”。

它有额外的特性，所以对某些人来说不够纯。

它还缺乏一些功能，因此对某些人来说还不够完整。

缺少的特性相对容易编写。查看类似这样的关于Python中的FP的帖子。