Use wizer to pre-initialize wasm artifact

app/App.hs

@@ -1,16 +1,15 @@
 module App (start) where
 
-import Control.Monad.IO.Class
+import GHC.Wasm.Prim
 import Language.Javascript.JSaddle (JSM)
 import SimpleCounter qualified
 import Snake qualified
-import System.Environment
 import TodoMVC qualified
 import TwoZeroFourEight qualified
 
-start :: JSM ()
-start =
-  liftIO (getEnv "EXAMPLE") >>= \case
+start :: JSString -> JSM ()
+start e =
+  case fromJSString e of
     "simplecounter" -> SimpleCounter.start
     "snake" -> Snake.start
     "todomvc" -> TodoMVC.start

app/Main.hs

@@ -1,19 +1,10 @@
-{-# LANGUAGE CPP #-}
-
-module Main (main) where
+module MyMain (main) where
 
 import App (start)
-
-#if wasi_HOST_OS
+import GHC.Wasm.Prim
 import Language.Javascript.JSaddle.Wasm qualified as JSaddle.Wasm
 
-foreign export javascript "hs_start" main :: IO ()
-
-main :: IO ()
-main = JSaddle.Wasm.run start
-#else
-import Language.Javascript.JSaddle.Warp qualified as JSaddle.Warp
+foreign export javascript "hs_start" main :: JSString -> IO ()
 
-main :: IO ()
-main = JSaddle.Warp.run 8081 start
-#endif
+main :: JSString -> IO ()
+main e = JSaddle.Wasm.run $ start e

app/Snake.hs

@@ -1,4 +1,3 @@
-{-# LANGUAGE CPP               #-}
 {-# LANGUAGE MultiWayIf        #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards   #-}

app/TodoMVC.hs

@@ -10,7 +10,6 @@
 {-# LANGUAGE MultiParamTypeClasses      #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE ExtendedDefaultRules       #-}
-{-# LANGUAGE CPP                        #-}
 
 -- from https://github.com/dmjio/miso/blob/master/examples/todo-mvc/Main.hs
 

frontend/build.sh

@@ -23,8 +23,9 @@ hs_wasm_path=$(wasm32-wasi-cabal list-bin ghc-wasm-miso-examples)
 if $dev_mode; then
     cp "$hs_wasm_path" dist/bin.wasm
 else
-    wasm-opt ${1+"$@"} "$hs_wasm_path" -o dist/bin.wasm
-    wasm-strip --keep-section=name dist/bin.wasm
+    wizer --allow-wasi --wasm-bulk-memory true --init-func _initialize -o dist/bin.wasm "$hs_wasm_path"
+    wasm-opt ${1+"$@"} dist/bin.wasm -o dist/bin.wasm
+    wasm-tools strip -o dist/bin.wasm dist/bin.wasm
 fi
 
 cp ./*.js dist

frontend/index.js

@@ -1,11 +1,8 @@
-import { WASI, OpenFile, File, ConsoleStdout } from "https://cdn.jsdelivr.net/npm/@bjorn3/browser_wasi_shim@0.2.19/dist/index.js";
+import { WASI, OpenFile, File, ConsoleStdout } from "https://cdn.jsdelivr.net/npm/@bjorn3/browser_wasi_shim@0.2.20/dist/index.js";
 import ghc_wasm_jsffi from "./ghc_wasm_jsffi.js";
 
 const args = [];
-const env = [
-  `EXAMPLE=${globalThis.example}`,
-  // `GHCRTS=-S`,
-];
+const env = [];
 const fds = [
   new OpenFile(new File([])), // stdin
   ConsoleStdout.lineBuffered((msg) => console.log(`[WASI stdout] ${msg}`)),
@@ -22,4 +19,4 @@ const { instance } = await WebAssembly.instantiateStreaming(fetch("bin.wasm"), {
 Object.assign(instance_exports, instance.exports);
 
 wasi.initialize(instance);
-await instance.exports.hs_start();
+await instance.exports.hs_start(globalThis.example);

ghc-wasm-miso-examples.cabal

@@ -8,8 +8,10 @@ executable ghc-wasm-miso-examples
       , aeson
       , base
       , containers
+      , ghc-experimental
       , hs2048
       , jsaddle
+      , jsaddle-wasm
       , miso
       , mtl
       , random
@@ -22,8 +24,4 @@ executable ghc-wasm-miso-examples
       SimpleCounter
       Snake
       TodoMVC
-    if os(wasi)
-      build-depends: jsaddle-wasm
-      ghc-options: -no-hs-main -optl-mexec-model=reactor "-optl-Wl,--export=hs_start"
-    else
-      build-depends: jsaddle-warp
+    ghc-options: -no-hs-main -optl-mexec-model=reactor "-optl-Wl,--export=hs_start"