WASM hello world

app/App.hs

@@ -0,0 +1,19 @@
+module App where
+
+import Reflex
+import Reflex.Dom.Core
+
+import Language.Javascript.JSaddle
+
+testWidget ::
+    ( DomBuilder t m
+    , DomBuilderSpace m ~ GhcjsDomSpace
+    , MonadHold t m
+    , PostBuild t m
+    ) =>
+    m ()
+testWidget = elAttr "div" ("class" =: "content") do
+    text "hello, world!"
+
+start :: JSM ()
+start = mainWidget testWidget

app/Main.hs

@@ -1,4 +1,12 @@
+{-# LANGUAGE CPP #-}
+
 module Main (main) where
 
+import App qualified
+import Language.Javascript.JSaddle
+import Language.Javascript.JSaddle.Wasm qualified as W
+
+foreign export javascript "hs_start" main :: IO ()
+
 main :: IO ()
-main = putStrLn "hi"
+main = W.run $ App.start