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TODO list single-page application using GHCJS
cabal-version: 3.0
name: ghcjs-demo
version: 1.0.0
license: BSD-3-Clause
executable ghcjs-demo
main-is: Main.hs
build-depends: base
, ghcjs-base
default-language: Haskell2010
<!DOCTYPE html>
<html>
<head>
<script language="javascript" src="build/rts.js"></script>
<script language="javascript" src="build/lib.js"></script>
<script language="javascript" src="build/out.js"></script>
</head>
<body>
<button id="click me" type="button">+</button>
</body>
<script language="javascript">
function replaceChildrenWorkaround(a, b) {
a.replaceChildren(...b)
}
</script>
<script language="javascript" src="build/runmain.js" defer></script>
</html>
{-# LANGUAGE BlockArguments #-}
{-# LANGUAGE OverloadedStrings #-}
module Main where
import Data.JSString (JSString)
import GHCJS.Foreign.Callback (Callback)
import GHCJS.Types (JSVal)
import JavaScript.Array (JSArray)
import qualified Data.JSString as JSString
import qualified GHCJS.Foreign.Callback as Callback
import qualified JavaScript.Array as Array
foreign import javascript unsafe "document.getElementById($1)"
getElementById :: JSString -> IO JSVal
foreign import javascript unsafe "$1.textContent = $2"
setTextContent :: JSVal -> JSString -> IO ()
foreign import javascript unsafe "$1.addEventListener($2, $3)"
addEventListener :: JSVal -> JSString -> Callback (IO ()) -> IO ()
foreign import javascript unsafe "document.createElement($1)"
createElement :: JSString -> IO JSVal
foreign import javascript unsafe "$1.before($2)"
before :: JSVal -> JSVal -> IO ()
foreign import javascript unsafe "$1.setAttribute($2, $3)"
setAttribute :: JSVal -> JSString -> JSString -> IO ()
foreign import javascript unsafe "replaceChildrenWorkaround($1, $2)"
replaceChildren_ :: JSVal -> JSArray -> IO ()
replaceChildren :: JSVal -> [JSVal] -> IO ()
replaceChildren a b = replaceChildren_ a (Array.fromList b)
foreign import javascript unsafe "$1.remove()"
remove :: JSVal -> IO ()
main :: IO ()
main = do
addButton <- getElementById "click me"
addCallback <- Callback.asyncCallback do
subtractButton <- createElement "button"
setTextContent subtractButton "-"
input <- createElement "input"
setAttribute input "type" "text"
div <- createElement "div"
replaceChildren div [ subtractButton, input ]
subtractCallback <- Callback.asyncCallback (remove div)
addEventListener subtractButton "click" subtractCallback
before addButton div
addEventListener addButton "click" addCallback
let
nixpkgs = builtins.fetchTarball {
url = "https://github.com/NixOS/nixpkgs/archive/21a3136d25e1652cb32197445e9799e6a5154588.tar.gz";
sha256 = "145d474g6dngvaiwq2whqdvaq14ba9pc5pvvcz4x8l2bkwbyn3hg";
};
overlay = pkgsNew: pkgsOld: {
haskell = pkgsOld.haskell // {
packages = pkgsOld.haskell.packages // {
ghcjs = pkgsOld.haskell.packages.ghcjs.override (old: {
overrides =
let
oldOverrides = old.overrides or (_: _: {});
sourceOverrides = pkgsNew.haskell.lib.packageSourceOverrides {
ghcjs-demo = ./.;
};
in
pkgsNew.lib.composeExtensions oldOverrides sourceOverrides;
});
};
};
};
config = { };
pkgs = import nixpkgs { inherit config; overlays = [ overlay ]; };
in
pkgs.haskell.packages.ghcjs.ghcjs-demo.env
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