Type of addition (+) in F#

Question

I just learned that OCAML have to have a . postfix for doing float arithmetic. An example would be 3. +. 4. which equals 7. (float). H

Answer 1

In addition to Brian´s answer and link:

https://github.com/fsharp/fsharp/blob/master/src/fsharp/FSharp.Core/prim-types.fs

I found some definitions in the code:

let inline (+) (x:int) (y:int) = (# "add" x y : int #)

and

let inline (+) (x: ^T) (y: ^U) : ^V = 
     AdditionDynamic<(^T),(^U),(^V)>  x y 
     when ^T : int32       and ^U : int32      = (# "add" x y : int32 #)
     when ^T : float       and ^U : float      = (# "add" x y : float #)
     when ^T : float32     and ^U : float32    = (# "add" x y : float32 #)
     ...

And the AdditionDynamic is defined here (loads of static stuff and CIL): https://github.com/fsharp/fsharp/blob/master/src/fsharp/FSharp.Core/prim-types.fs#L2374

Fun stuff:

(# "add" 1 2 : int32 #)

works, and gives 3 as output (with a warning saying you shouldn't do this.)