kek

t.js

ar t = require('./test');
// a returns print function "b" increment function
var a = t("a");
var b = t("b");

a();
b();
setTimeout(a,100);
setTimeout(a,200);
setTimeout(b,150);
setTimeout(b,300);
setTimeout(a,350);

test.js

module.exports = function(which) {
	var self = this;
	this.i = 0;
	var a = function() {
		console.log("i: "+self.i);
	}
	var b = function() {
		self.i++;
	}
	if(which == "a") {
		return a;
	} else {
		return b;
	}
	
};

module.exports = function(which) {
console.log("Init:"+which);
var self = this;
this.from = which;
this.i = 0;
var a = function() {
console.log("i: "+self.i+" which:"+self.from);
}
var b = function() {
self.i++;
}
if(which == "a") {
return a;
} else {
return b;
}

};