How to cancel an agent

agent-cancel.fsx

#quit

#load "LoadServer.fsx"

open System
open System.Threading
open LoadServer.Watcher

//  Agents can be cancelled if you want to stop a runaway
//  process

type Agent<'a> = MailboxProcessor<'a>

// This start function will create an agent and provide it
//  with a cancellation token so we can stop it.
let startAgent(f) = 
    let cts = new CancellationTokenSource()
    let agent = new Agent<_>(f, cts.Token)
    agent.Start()
    //  We return the agent and the token
    (agent, cts)


//  Now lets create the agent and capture the token
let (agent1, cancelToken) = startAgent<int> <| fun inbox ->
    async {
        for x in 1..1000 do
            do! Async.Sleep(1000)
            print(("Agent", x)) |> ignore
    }

//  Let's call the cancel method
cancelToken.Cancel()

//  That's it.  Do you have any questions about Agents
//  you'd like to see demoed?  Just mention me.

LoadServer.fsx

//  1. Create a project and add Steego.FsPad as a Nuget dependency
//  2. Build your project and set this folder to your output
#I "bin/Debug/net461/"

#r "FSharp.Core.dll"
#r "Suave.dll"
#r "Steego.FsPad.dll"

module Watcher = 

    //  Start the web server (websockets)
    let web = FsPad.Web(3000)
    //  Define a hacky printer function
    let print(x) = web.Dump(x, 5); web.Dump(x, 5); sprintf "%A" x

    //  Register it with fsi
    do fsi.AddPrinter(print)