F # style - prefer () or <|

Question

Which of these two alternatives do you most often use, and which is more "idiomatic"?

• f arg (obj.DoStuff ())
• f arg <| obj.DoStuff ()

Answer 1

In general, I do not know that one or the other is more idiomatic.

Personally, the only time I use <| with a raise:

raise <| new FooException("blah")

In addition, I always use parens. Note that since most F # codes use curries functions, this usually does not imply any “extra” pairs:

f arg (g x y)

This is when you get into non-card functions and constructors, and also the fact that it starts to become less pretty:

f arg (g(x,y))

, , , F #, ;

f g()

,

f g ()

,

f (g())

( ). , .

Answer 2

, |> , F # .

,

[1; 2; 3] |> (fun x -> x.Length*2)

,

(fun x -> x.Length*2) [1; 2; 3]

" ".

Answer 3

() , , , < | | , () .

Answer 4

, | > , .