我在这里看到很多关于函数式语言的讨论。为什么你要使用传统语言而不是传统语言呢?他们在哪些方面做得更好?他们更不擅长什么?理想的函数式编程应用程序是什么?


当前回答

大学里并没有真正教授(或者现在有吗?)

我不知道现在的情况,但在90年代中期,我在计算机科学课程中学习了米兰达语言和Lisp语言。尽管从那以后没有使用纯函数语言,但它影响了我解决问题的方式。

大多数应用程序都足够简单,可以用正常的面向对象方法解决

在90年代中期的CS课程中,面向对象(使用Eiffel教授)的教学与函数式编程相当。两者在当时都是非主流的。面向对象现在可能是“正常”的,但过去并非如此。

我很有兴趣看看f#是否是将FP推向主流的东西。

其他回答

微软正在Visual Studio上大力推广f#的下一个版本。它是一种像Scala一样的混合语言,并且可以很好地与。net框架的其余部分集成。我认为许多微软公司将使用它来加速高度并行的数据处理应用程序和功能的开发。

I don't know whether it will catch on or not, but from my investigations, a functional language is almost certainly worth learning, and will make you a better programmer. Just understanding referential transparency makes a lot of design decisions so much easier- and the resulting programs much easier to reason about. Basically, if you run into a problem, then it tends to only be a problem with the output of a single function, rather than a problem with an inconsistant state, which could have been caused by any of the hundreds of classes/methods/functions in an imparative language with side effects.

FP的无状态本质更自然地映射到web的无状态本质,因此函数式语言更容易让自己更优雅,更RESTFUL的web应用程序。与JAVA和. net框架形成鲜明对比的是,它们需要在本质上无状态的功能平台(如web)上使用VIEWSTATE和SESSION键来维护应用程序状态,并维护有状态命令语言的抽象(有时相当容易泄漏)。

而且,应用程序越无状态,就越容易进行并行处理。如果你的网站很受欢迎,这对网络来说非常重要。向站点添加更多硬件以获得更好的性能并不总是那么简单。

为什么函数式编程很重要

一些想法:

The debate between FP and imperative programming (OO, structured, etc), has been raging since Lisp versus Fortran. I think you pose excellent questions but recognize that they are not especially new. Part of the hoopla over FP is that we seem to be recognizing that concurrency is very difficult, and that locks and other mechanisms in OO (e.g. Java) are just one solution. FP offers a refreshing sea change with ideas such as Actors and the power of stateless computing. To those wrestling with OO, the landscape seems highly appealing. Yes, schools teach FP. In fact, the University of Waterloo and others offer Scheme in first year classes (reference here). Regarding the average programmer, I'm sure that the same arguments were given against C++ back in the early 1990s. And look what happened. If businesses can gain an advantage via a technology, you can bet that people will receive training.

这并不是说这是板上钉钉的事,也不是说在3-5年内不会出现反弹(一如既往)。然而,朝着计划生育的趋势是有好处的,值得关注。

Slava Akhmechet写了一篇很棒的文章,叫做《函数式编程》(顺便说一下,正是这篇文章让我开始接触FP)。在FP带来的好处中,他非常规地强调了以下几点(我认为这有助于软件工程师的吸引力):

单元测试 调试 并发性 热码部署 机器辅助证明与优化

然后继续讨论FP中更多传统讨论的方面的优点,如高阶函数、咖喱、惰性求值、优化、抽象控制结构(尽管没有讨论单子)、无限数据结构、严格性、延续、模式匹配、闭包等。

强烈推荐!