Ceylon Express attempt

express.ceylon

dynamic Express {}

Application requireExpressAndCallConstructor() {
	dynamic { return require("express")(); }
}

dynamic Request {}

dynamic Response {
	shared formal void send(String string);
}

dynamic Application {
	
	shared formal void get(String path, 
		Anything(Request, Response)|Null|Anything(Request, Response)[] callbacks=null);
	
	shared formal Server listen(Integer integer, Anything() callable);

}

nodejs.ceylon

dynamic Path {
	
}

dynamic Server {
	
	shared formal dynamic address();
	
}

run.ceylon

"Run the module `my.express`."
shared void run() {
    
	Application app = requireExpressAndCallConstructor();
    
    	app.get("/", (Request req, Response res) {
        	return res.send("Hello world!");
	});
	
	Server server = app.listen(3000, () {
		
		//dynamic host = server.address().address;
		//dynamic port = server.address().port;
		
		dynamic {
			console.log(
				"Example app listening..."// at http://%s:%s",
				//host,
				//port
			);
		}
		return nothing;
	});
}

I've updated the code per your suggestions @chochos and I am now getting a new error that I don't understand 😕

if(type.t.$$.T$name in obj.getT$all()){
                           ^
TypeError: Cannot use 'in' operator to search for 'my.express::Application' in undefined
    at is$ (C:\Users\madca_000\.eclipse\org.eclipse.platform_4.4.1_1167611518_win32_win32_x86_64\plugins\com.redhat.ceylon.dist.repo_1.1.0.v20141013-1416\repo\ceylon\language\1.1.0\ceylon.language-1.1.0.js:188:28)
    at Object.dre$$ (C:\Users\madca_000\.eclipse\org.eclipse.platform_4.4.1_1167611518_win32_win32_x86_64\plugins\com.redhat.ceylon.dist.repo_1.1.0.v20141013-1416\repo\ceylon\language\1.1.0\ceylon.language-1.1.0.js:634:5)
    at requireExpressAndCallConstructor (C:\Users\madca_000\eclipse\ceylon-express-raw\modules\my\express\1.0.0\my.express-1.0.0.js:76:17)
    at run (C:\Users\madca_000\eclipse\ceylon-express-raw\modules\my\express\1.0.0\my.express-1.0.0.js:13:13)
    at [eval]:1:292
    at Object.<anonymous> ([eval]-wrapper:6:22)
    at Module._compile (module.js:456:26)
    at evalScript (node.js:536:25)
    at startup (node.js:80:7)
    at node.js:906:3

I know it has to do with calling the return of require (i.e., require("express")(); ) but that is how the JavaScript is done. Here is the example given in the Express.js docs:

var express = require('express')
var app = express()

app.get('/', function (req, res) {
  ...
})

var server = app.listen(3000, function () {

  ...

})

And when I don't call the return (i.e., require("express"); ), I get this:

    $3i.$_get("/",m$3h.$JsCallable((function($3j,$3k){
        ^
TypeError: Object function createApplication() {
  var app = function(req, res, next) {
    app.handle(req, res, next);
  };

  mixin(app, proto);
  mixin(app, EventEmitter.prototype);

  app.request = { __proto__: req, app: app };
  app.response = { __proto__: res, app: app };
  app.init();
  return app;
} has no method '$_get'
    at run (C:\Users\madca_000\eclipse\ceylon-express-raw\modules\my\express\1.0.0\my.express-1.0.0.js:14:9)
    at [eval]:1:292
    at Object.<anonymous> ([eval]-wrapper:6:22)
    at Module._compile (module.js:456:26)
    at evalScript (node.js:536:25)
    at startup (node.js:80:7)
    at node.js:906:3