Partial application in haskell with multiple arguments

Given some function f(x1,x2,x3,..,xN) it is often useful to apply it partially in several places. For example, for N=3 we could define g(x)=f(1,x,3). However, the standard partial application in Haskell does not work this way and only allows us to partially apply a function by fixing its first arguments (because all functions actually only take one argument). Is there any simple way to do something like this:

g = f _ 2 _
g 1 3

with output the value of f 1 2 3 ? Of course we could do a lambda-function

g=(x1 x3 -> f x1 2 x3)

but I find this quite unreadable. For example, in Mathematica it works like this, which I find quite nice:

g=f[#1,2,#2]&
g[1,3]

with output f[1,2,3] .

Edit: Maybe I should say somehting more about the motivation. I would like to use such partially applied functions in point-style compositions, ie, in expressions like this:

h = g. f _ 2 . k

to get h 3 = g(f(k(3),2)) .

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你可以阅读这个关于如何改变参数顺序的问题，然后使用部分应用程序，但是目前在Haskell中最干净和最清晰的方法就是直接：

g x y = f x 2 y

---

No, the simplest way is to define a lambda. You can probably try and play with flip , but I doubt it would be cleaner and simpler than a lambda. Especially for longer list of arguments.

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The simplest (and canonical) way is to define a lambda. It is much more readable if you use meaningful argument names where possible

getCurrencyData :: Date -> Date -> Currency -> IO CurrencyData
getCurrencyData fromDate toDate ccy = {- implementation goes here -}

you can define your new function with lambda syntax

getGBPData = from to -> getCurrencyData from to GBP

or without it

getGBPData from to = getCurrencyData from to GBP

or you can use combinators, but I think this is quite ugly

getGBPData = from to -> getCurrencyData from to GBP
           = from to -> flip (getCurrencyData from) GBP to
           = from    -> flip (getCurrencyData from) GBP
           = from    -> (flip . getCurrencyData) from GBP
           = from    -> flip (flip . getCurrencyData) GBP from
           =             flip (flip . getCurrencyData) GBP

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