Files
functional-programming-snake/fsharp/solutions/Pong/App.fs
T
Lucas WintherandClaude Fable 5.2 edd57f0148 feat(course): audit fixes and twelve extensions (Modules 7b, 12, 13)
Audit pass:
- Frame rule counts frames since the last move, so every step lasts
  exactly movesEvery(score) frames, also right after a speed-up
- clampTime + MAX_GAP_MS: a hidden tab no longer replays the whole gap
- Pong Restart keeps held keys
- Fact corrections (mulberry32 output coverage, Haskell IO, uniform)
- New fixture cases from a mutation analysis

Extensions (all three tracks, shared fixtures, course text):
- Turn queue (Exercise 10.6), persisted high score (10.7),
  replay viewer (10.8), play() end-to-end helper (9.5)
- Optional State (4.7) and optional Module 7b, stack-safe IO
- Module 12, property-based testing with generators, shrinking,
  invariants and a model-based oracle
- Module 13, Conway's Life with a Click event
- JS type checking via jsconfig, JSDoc and types.d.ts
- Maintainer tools: scripts/mutate.mjs, scripts/typecheck-js.sh,
  Playwright end-to-end suite (e2e/, scripts/e2e.sh)

Docs: docs/contract.md is the canonical contract; specs and build log
under docs/superpowers.

Verified: JS 728, Scala 689, F# 691 unit tests; stubs and progression
M01-M13 and M07b; 176 end-to-end tests on Chromium and WebKit.

Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
2026-11-11 12:05:29 +01:00

40 lines
1.4 KiB
FSharp

/// m11 pong app: the same wiring as App.fs (streams in, drawings out), reusing the course's modules.
module Snake.Pong.App
open Snake
open Snake.IO
open Snake.Stream
open Snake.Pong.Model
open Snake.Pong.Rules
open Snake.Pong.View
let FRAME_MS_PONG = 30L
let private paddleKey (key: string) : Paddle option =
match key with
| "ArrowUp" | "w" | "W" -> Some Paddle.Up
| "ArrowDown" | "s" | "S" -> Some Paddle.Down
| _ -> None
let pongKey (isDown: bool) (key: string) : PongAction option =
match paddleKey key with
| Some p -> Some(if isDown then PongAction.Press p else PongAction.Release p)
| None -> if isDown && (key = "r" || key = "R") then Some PongAction.Restart else None
let pongActions: Stream<PongAction> =
Stream.merge
(Stream.merge
(Stream.interval FRAME_MS_PONG |> Stream.map (fun _ -> PongAction.Frame))
(Stream.keyDowns |> Stream.choose (pongKey true)))
(Stream.keyUps |> Stream.choose (pongKey false))
let pongStates (seed: uint32) (actions: Stream<PongAction>) : Stream<PongState> =
actions |> Stream.scan pongUpdate (initialPong seed) |> Stream.startWith (initialPong seed)
let pongMain () : IO<Stream<IO<unit>>> =
IO.randomSeed ()
|> IO.map (fun seed ->
pongStates seed pongActions
|> Stream.map (fun state -> IO.drawScene (pongView state))
|> Stream.clampTime App.MAX_GAP_MS)