Add Striped reading

equinox-sync/Sync/Infrastructure.fs

@@ -1,6 +1,7 @@
 [<AutoOpen>]
 module private SyncTemplate.Infrastructure
 
+open Equinox.Store // AwaitTaskCorrect
 open System
 open System.Threading
 open System.Threading.Tasks
@@ -17,3 +18,23 @@ type Async with
             let rec callback _ = Task.Run(fun () -> if Interlocked.Increment isDisposed = 1 then d.Dispose() ; sc ()) |> ignore
             and d : IDisposable = Console.CancelKeyPress.Subscribe callback
             in ())
+
+type SemaphoreSlim with
+    /// F# friendly semaphore await function
+    member semaphore.Await(?timeout : TimeSpan) = async {
+        let! ct = Async.CancellationToken
+        let timeout = defaultArg timeout Timeout.InfiniteTimeSpan
+        let task = semaphore.WaitAsync(timeout, ct) 
+        return! Async.AwaitTaskCorrect task
+    }
+
+module Queue =
+    let tryDequeue (x : System.Collections.Generic.Queue<'T>) =
+#if NET461
+        if x.Count = 0 then None
+        else x.Dequeue() |> Some
+#else
+        match x.TryDequeue() with
+        | false, _ -> None
+        | true, res -> Some res
+#endif