Even Odd in F#

Published on 08 April 2026 (Updated: 08 April 2026)

Welcome to the Even Odd in F# page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

open System

let usage = "Usage: please input a number"

module EvenOdd =
    let run n = if n % 2 = 0 then "Even" else "Odd"

module Helpers =
    let (|Int|_|) (s: string) =
        match s.Trim() |> Int32.TryParse with
        | true, n -> Some n
        | false, _ -> None

    let parseArgs argv =
        match argv with
        | [| Int n |] -> Ok n 
        | _ -> Error usage

    let handleResults =
        function
        | Ok result ->
            printfn "%s" result
            0
        | Error msg ->
            eprintfn "%s" msg
            1

[<EntryPoint>]
let main argv =
    argv
    |> Helpers.parseArgs
    |> Result.map EvenOdd.run
    |> Helpers.handleResults

Even Odd in F# was written by:

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

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