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Async loop with ref variables?
websharperasyncrefloop

I'm trying to run a asnychronous loop on my web page. There seems to be a problem with ref variables that I don't understand.

This loop works like I would expect:

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    async {
        let x = 0
        while true do
            let y = x
            JS.Alert(y.ToString())
            do! Async.Sleep 5000
    } |> Async.Start

However, as soon as I introduce a ref variable, the loop stops working:

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    async {
        let x = ref 0
        while true do
            let y = !x
            JS.Alert(y.ToString())
            x := !x + 1
            do! Async.Sleep 5000
    } |> Async.Start

Is there a problem with my understanding (most likely!) or WebSharper?

.

I'm not exactly sure what the problem is but your code seems to work fine on tryws: http://try.websharper.com/snippet/00007n. Do you see any errors in the console?

By on 4/8/2016 6:02 AM ()

Could it be a problem in CloudSharper? I added the example to the default SinglePageApplication, like this:

namespace SinglePageApplication

open WebSharper

<JavaScript> module Client =

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open WebSharper.JavaScript
open WebSharper.Html.Client

async {
    let x = ref 0
    while true do
        let y = !x
        JS.Alert(y.ToString())
        x := !x + 1
        do! Async.Sleep 5000
} |> Async.Start    

let content =
    Button [Text "Click me!"]
    |>! OnClick (fun _ _ ->
        JS.Alert "Clicked!")

let Main =
    Console.Log("Running JavaScript Entry Point..")
    content.AppendTo "my-container"

When I click the button, I get an Alert, but I never see any Alerts from the async loop. I verified that it works fine in try.websharper.

By on 4/8/2016 9:06 AM ()

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