How can I use a user inputted value in my Function in F#

Question

So I\'m trying to make a simple factorial function in F# that uses a value inputted from the user (using the console, I don\'t know if that makes any difference) but I can\'

Answer 1

F# does no automatic conversions for you, so you'll need to parse the string:

open System

let rec fact x =
    if x < 1 then 1
    else x * fact (x - 1)

let input = Console.ReadLine()
Console.WriteLine(fact (Int32.Parse input))

In theory you would need to convert back to string to print it, but it works because there is an overload for Console.WriteLine that takes an integer and does the conversion.