Prepare timeflies for the new asyncio mainloop (#95)

Author: dbrattli

.config/dotnet-tools.json

@@ -9,7 +9,7 @@
       ]
     },
     "fable": {
-      "version": "4.2.1",
+      "version": "4.2.2",
       "commands": [
         "fable"
       ]

examples/timeflies/Program.fs

@@ -6,6 +6,7 @@ open FSharp.Control
 open Fable.Python
 open Fable.Python.TkInter
 open Fable.Python.Queue
+open Fable.Python.AsyncIO
 
 type Msg =
     | Place of label: Label * x: int * y: int
@@ -30,7 +31,6 @@ let workerAsync (mb: MailboxProcessor<Event>) =
     messageLoop ()
 
 let agent = MailboxProcessor<TkInter.Event>.Start (workerAsync)
-
 let frame = Frame(root, width = 800, height = 600, bg = "white")
 frame.bind ("<Motion>", agent.Post) |> ignore
 frame.pack ()
@@ -47,7 +47,7 @@ let stream =
 let sink (ev: Notification<Label * int * int>) =
     async {
         match ev with
-        | OnNext (label, x, y) -> queue.put (Place(label, x, y))
+        | OnNext (label, x, y) -> label.place (x, y)
         | OnError (err) -> printfn $"Stream Error: {err}"
         | _ -> printfn "Stream Completed!"
     }
@@ -56,22 +56,11 @@ let mainAsync =
     async {
         use! disposable = stream.SubscribeAsync(sink)
 
-        let rec update () =
-            let size = queue.qsize ()
-
-            for _ in 1..size do
-                let msg = queue.get (false)
-
-                match msg with
-                | Place (label, x, y) -> label.place (x, y)
-                | _ -> ()
-
-            match size with
-            | n when n > 0 -> root.after (1, update)
-            | _ -> root.after (10, update)
+        while true do
+            while root.dooneevent(int Flags.DONT_WAIT) do
+                ()
 
-        root.after (1, update)
-        root.mainloop ()
+            do! Async.AwaitTask(asyncio.create_task(asyncio.sleep(0.005)))
     }
 
 [<EntryPoint>]

examples/timeflies/TimeFlies.fsproj

@@ -2,15 +2,18 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net7.0</TargetFramework>
     <WarnOn>3390;$(WarnOn)</WarnOn>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Program.fs" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Fable.Python" Version="4.0.0-theta-*" />
-    <PackageReference Include="Fable.Core" Version="4.0.0-theta-*" />
+    <PackageReference Include="Fable.Python" Version="4.*" />
+    <PackageReference Include="Fable.Core" Version="4.*" />
     <PackageReference Include="FSharp.Control.AsyncRx" Version="1.6.5" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\Fable.Python.fsproj" />
+  </ItemGroup>
 </Project>

examples/timeflies/pyproject.toml

@@ -7,7 +7,7 @@ authors = ["Dag Brattli <[email protected]>"]
 license = "MIT"
 
 [tool.poetry.dependencies]
-python = "^3.9"
+python = "^3.11"
 fable-library = ">=0.8.0"
 #fable-python = "*"
 #fsharp-control-async-rx = "*"

src/stdlib/TkInter.fs

@@ -2,6 +2,9 @@ module Fable.Python.TkInter
 
 open Fable.Core
 
+type Flags =
+    | DONT_WAIT = 2
+
 [<Import("Event", "tkinter")>]
 type Event =
     abstract member x: int
@@ -33,6 +36,7 @@ type Tk(screenName: string option) =
     member _.update() = nativeOnly
     member _.mainloop() = nativeOnly
     member _.after(msecs: int, callback: unit -> unit) = nativeOnly
+    member _.dooneevent(flags: int) = nativeOnly
 
 [<Import("Frame", "tkinter")>]
 type Frame(master: Misc) =

src/stdlib/asyncio/Tasks.fs

@@ -5,6 +5,9 @@ open Fable.Core
 type Task<'T> =
     inherit Future<'T>
 
+type Task =
+    inherit Future<unit>
+
 type Coroutine<'T> =
     inherit Awaitable<'T>
 
@@ -15,7 +18,12 @@ type Coroutine<'T> =
 
 type IExports =
     abstract create_task<'T> : fn: Coroutine<'T> -> Task<'T>
-    abstract sleep: seconds: float -> result: 'T -> Future<'T>
+    /// Translates a Python Task to a System.Threading.Tasks.Task
+    abstract create_task: task: Task -> System.Threading.Tasks.Task
+    /// Translates a Python Task<'T> to a System.Threading.Tasks.Task<'T>
+    abstract create_task: task: Task<'T> -> System.Threading.Tasks.Task<'T>
+    abstract sleep: seconds: float -> Task
+    abstract sleep: seconds: float * result: 'T -> Task<'T>
     abstract run<'T> : main: Awaitable<'T> -> 'T
     abstract run<'T> : main: System.Threading.Tasks.Task<'T> -> 'T
 

test/TestAsyncIO.fs

@@ -19,3 +19,19 @@ let ``test builder run int works`` () =
     let result = asyncio.run(tsk)
     result |> equal 42
 
+[<Fact>]
+let ``test sleep works`` () =
+    let tsk = task {
+        do! asyncio.create_task(asyncio.sleep(0.1))
+        return 42
+    }
+    let result = asyncio.run(tsk)
+    result |> equal 42
+
+[<Fact>]
+let ``test sleep with value works`` () =
+    let tsk = task {
+        return! asyncio.create_task(asyncio.sleep(0.1, 42))
+    }
+    let result = asyncio.run(tsk)
+    result |> equal 42