哈斯克尔重定向
F# 工作让我了解了 Haskell。我目前正在阅读我强烈推荐的本教程的第 7 章。 不过问题很快。也许我有点超前了，我会在以后的章节中找到答案，但是，如果函数像 F# 中那样只接受一个参数，有没有一种方法可以反转函数及其参数的位置。 因此，例如，在 F# 中，如果您有一个名为 digitalToInt 的函数（就像在 Haskell 中所做的那样），您可以执行以下操作：
3 |> digitalToInt
我知道如何使用反引号，但那是专门针对二进制函数的。一元函数有类似的东西吗？
Working in F# has lead me to learn about Haskell. I'm currently on chapter 7 of this tutorial which I HIGHLY recommend.
Quick question though. Maybe I'm getting ahead of myself and I'll find the answer in future chapters but, is there a way to reverse the position of the function and it's arguments if the function only takes one argument like in F#.
So, for example, in F# if you had a function called digitToInt (as you do in Haskell), you could do the following:
3 |> digitToInt
I know about using back ticks, but that's specifically for binary functions. Is there anything similar for unary functions?
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一种方法是定义一个中缀函数
(|>)，它接受一个值和一个函数，并调用该函数并将其传递给该值，如下所示：然后您可以像在您的代码中一样使用它例子：
One way to do that could be defining an infix function
(|>)that take a value and a function and calls the function passing it the value like this:Then you can use it exactly like in your example:
你可以按照peoro的建议去做，效果很好。不过，我建议不要这样做。 “阅读”Haskell 的正常方式就像一个句子——从左到右，动词在开头，主语在结尾。通常，您会得到像
f 这样的链式组合。 g。 q. r$x。使用一元运算符，您可以得到f =<< g =<< x（或(f <=< g) =<< x），并且使用应用程序，您会得到f <$>; x<*> y* z 。因此，颠倒事物的正常顺序并不一定是惯用的。顺便说一句，据我所知，F# 选择相反的运算符的原因是它与 Visualstudio 自动完成功能配合得非常好——如果您输入了正在操作的值，那么它的类型就可以确定选择可以对其进行操作的内容。这种工具支持非常棒，这将是采用替代风格的一个很好的论据。
You can do what peoro suggests and it works fine. However, I'd advise against it. The normal way to "read" Haskell is like a sentence -- left to right, with verbs at the beginning and the subject at the end. Typically you get a chained composition like
f . g. q . r $ x. With monadic operators you getf =<< g =<< x(or(f <=< g) =<< x) and with applicatives you getf <$> x <*> y <*> z. So reversing the normal order of things is not necessarily idiomatic.By the way, the reason, so I've heard, that F# chose the opposite operator is that it works very very nicely with visualstudio autocomplete -- if you've typed in the value you're operating on, then its type can determine choices for what can operate on it. That sort of tooling support is awesome, and it would be a good argument for adopting an alternate style.
我不认为 Haskell 有一个标准的运算符（我可能是错的），但你当然可以定义一个。一个有点相关的概念是
$运算符，它允许您在编写一系列应用程序时去掉括号（这是在 F# 中使用|>的原因之一）。不同之处在于$不会颠倒顺序：BTW：在 Haskell 中查找此类内容的一个绝佳方法是使用 Hoogle。例如：
I don't think that Haskell has a standard operator for this (I may be wrong), but you can certainly define one. A somewhat related concept is the
$operator that allows you to get rid of parentheses when writing a series of applications (which is one reason for using|>in F#). The difference is that$doesn't reverse the order:BTW: A fantastic way to find out things like this in Haskell is to use Hoogle. For example: