F# Actor Example

greeter.fsx

open System

type Message =
    | Hi
    | Greet of string

let greeterActor = MailboxProcessor.Start(fun inbox ->
    
    // the message processing function
    let rec messageLoop() = async{
    
        // read a message
        let! msg = inbox.Receive()
        
        // process the message
        match msg with
        | Hi -> 
            printfn "Hi!"
        | Greet msg -> 
            printfn $"Hello, {msg}!"
            
        // // loop to top    
        return! messageLoop()
        }
    // start the loop
    messageLoop()
    )

greeterActor.Post Hi // send a Hi message to the actor's message queue
greeterActor.Post (Greet "world") // send a Greet message to the actor's message queue