ghcjs-commonjs

ghcjs-commonjs is a work-in-progress collection of little hacks to make GHCJS generated JavaScript and CommonJS integration less troublesome.

This hasn't been tested in production yet, so try the examples and report any issues that you have

We provide the following tools:

• ghcjs-require - Calling Haskell from Node.js and CommonJS
• ghcjs-commonjs - Exposing Haskell to be called from CommonJS
• ghcjs-register - require('./MyHaskellModule.hs')
• ghcjs-loader - A webpack loader for GHCJS

ghcjs-require

Utilities for loading GHCJS .jsexes from CommonJS land.

Callling Haskell from JavaScript

This is main.js:

const ghcjsRequire = require('ghcjs-require');
const Main = ghcjsRequire(module, './Main.jsexe');
// ^^ This is a function that boots the Haskell RTS
Main(({wrapped}) => { // <- This callback is executed after the RTS is loaded
  wrapped.someFunction().then(() => console.log('someFunction is over'));
  // ^^ This function was generated, it'll call Haskell code asynchronously and
  //    return a promise to the result (the result needs to be a JavaScript
  //    value)
});

This is Main.hs:

import Control.Concurrent (threadDelay)
import qualified GHCJS.CommonJS as CJS (exportMain, pack)
someFunction = do
    putStrLn "Waiting for a second"
    threadDelay (1000 * 1000)
    putStrLn "Done!"
main = CJS.exportMain [ "someFunction" `CJS.exports` someFunction
                      ]

ghcjs-register

On the likes of coffee-script/register or babel-register:

require('ghcjs-register');
const Main = require('./Main.hs');

ghcjs-loader

This is a webpack loader for GHCJS. See the examples.

License

All code under this repository is licensed under the MIT license.