// source https://jsbin.com/vaxaqe

index.html

<script id="jsbin-javascript">
function User(){
	var username, password;

	function doLogin(user,pw) {
		username = user;
		password = pw;
	}

	var publicAPI = {
		login: doLogin
	};

	return publicAPI;
}

var fred = User();

fred.login( "fred", "12Battery34!" );
</script>


<script id="jsbin-source-javascript" type="text/javascript">function User(){
	var username, password;

	function doLogin(user,pw) {
		username = user;
		password = pw;
	}

	var publicAPI = {
		login: doLogin
	};

	return publicAPI;
}

var fred = User();

fred.login( "fred", "12Battery34!" );</script>

jsbin.vaxaqe.js

function User(){
	var username, password;

	function doLogin(user,pw) {
		username = user;
		password = pw;
	}

	var publicAPI = {
		login: doLogin
	};

	return publicAPI;
}

var fred = User();

fred.login( "fred", "12Battery34!" );