add example

README.md

@@ -48,7 +48,7 @@ A default Promise constructor can be used to create a self-resolving deferred/pr
     var Promise = require("promise").Promise;
     var promise = new Promise();
     asyncOperation(function(){
-      Promise.resolve("succesful result");
+      promise.resolve("succesful result");
     });
     promise -> given to the consumer
 

example-defer.js

@@ -0,0 +1,19 @@
+var defer = require("./promise").defer;
+
+function asyncOperation() {
+	var dfd = defer();
+	setTimeout(function(){
+		if("pending" == dfd.state()) {
+			dfd.resolve("succ result");
+			// dfd.reject(new Error("an err"));
+		}
+	}, 5000);
+	return dfd.timeout(3000);
+	// return dfd.promise;
+}
+
+asyncOperation().then(function(result){
+	console.log("on succ: ", result);
+}, function(err) {
+	console.log("on fail: ", err);
+});

example-promise.js

@@ -0,0 +1,17 @@
+var promise = require("./promise");
+
+promise.execute(function(callback){
+	asyncOperation(callback);
+}).then(function(result){
+	console.log("on succ: ", result);
+}, function(err) {
+	console.log("on fail: ", err);
+});
+
+
+function asyncOperation(callback) {
+	setTimeout(function(){
+		callback(null, "succ result");
+		//callback(new Error("an err"));
+	}, 2000);
+};

promise.js

@@ -266,6 +266,17 @@ function Deferred(canceller){
       reject(error);
     }
   }
+
+  this.state = function(){
+    var ret = "pending";
+    if(isError) {
+      ret = "rejected";
+    } else if(finished) {
+      ret = "resolved";
+    }
+    return ret;
+  }
+
   freeze(promise);
 };