[Haskell-cafe] Syntax proposal for "reverse apply"/"pipeline apply" (flip ($))

[Richard A. O'Keefe]

On 18/04/2014, at 1:11 AM, Alexey Muranov wrote:

> I do not know F#, and maybe i am missing something, but assuming that
> 
>    x |> f |> g == (x |> f) |> g
> 
> and 
> 
>    g <| f <| x == g <| (f <| x)
> 
> what are
> 
>    x |> f <| y
> 

This is the same as (f x) y.  Determined by experiment:

	let h x y = (x,y) ;;
	1 |> h <| 2 ;;
=>	val it : int * int = (1, 2)

(f y) x would give the answer (2, 1).

> 
>    g <| x |> f

This is f (g x).  Determined by experiment:
	let f x = x * 2 ;;
	let g x = x + 1 ;;
	g <| 1 |> f ;;
=>	val it : int = 4

g (f 1) would give the answer 3.