Added promise support

.lint

@@ -24,7 +24,9 @@ predef+ setTimeout, clearTimeout
 
 ./test/index.js
 ./test/ext/max-age.js
-predef+ setTimeout
+predef+ setTimeout, Promise, global
+./test/ext/promise.js
+predef+ Promise, setTimeout, global
 
 ./benchmark
 sub

ext/dispose.js

@@ -11,7 +11,7 @@ var callable   = require('es5-ext/object/valid-callable')
 extensions.dispose = function (dispose, conf, options) {
 	var del;
 	callable(dispose);
-	if (options.async && extensions.async) {
+	if ((options.async && extensions.async) || (options.promise && extensions.promise)) {
 		conf.on('deleteasync', del = function (id, result) {
 			apply.call(dispose, null, slice.call(result.args, 1));
 		});

ext/promise.js

@@ -0,0 +1,50 @@
+// Support for functions returning promise
+
+'use strict';
+
+var nextTick = require('next-tick')
+
+  , create = Object.create;
+
+require('../lib/registered-extensions').promise = function (tbi, conf) {
+	var cache = create(null);
+
+	// After not from cache call
+	conf.on('set', function (id, __, promise) {
+		promise.then(function () {
+			// nextTick avoids error interception
+			nextTick(function () {
+				cache[id] = promise;
+				conf.emit('setasync', id, 1);
+			});
+		}, function () {
+			nextTick(function () {
+				conf.delete(id);
+			});
+		});
+	});
+
+	// From cache (sync)
+	conf.on('get', function (id, args, context) {
+		conf.emit('getasync', id, args, context);
+	});
+
+	// On delete
+	conf.on('delete', function (id) {
+		var result;
+		// If false, we don't have value yet, so we assume that intention is not
+		// to memoize this call. After value is obtained we don't cache it but
+		// gracefully pass to callback
+		if (!cache[id]) return;
+		result = cache[id];
+		delete cache[id];
+		conf.emit('deleteasync', id, result);
+	});
+
+	// On clear
+	conf.on('clear', function () {
+		var oldCache = cache;
+		cache = create(null);
+		conf.emit('clearasync', oldCache);
+	});
+};

index.js

@@ -26,6 +26,7 @@ module.exports = function (fn/*, options*/) {
 
 	// Assure extensions
 	if (options.async) require('./ext/async');
+	if (options.promise) require('./ext/promise');
 	if (options.dispose) require('./ext/dispose');
 	if (options.maxAge) require('./ext/max-age');
 	if (options.max) require('./ext/max');

lib/configure-map.js

@@ -49,7 +49,7 @@ module.exports = function (original, length, options) {
 				throw customError("Circular invocation", 'CIRCULAR_INVOCATION');
 			}
 			cache[id] = result;
-			if (setListeners) conf.emit('set', id);
+			if (setListeners) conf.emit('set', id, null, result);
 			return result;
 		}, memLength);
 	} else if (length === 0) {
@@ -65,7 +65,7 @@ module.exports = function (original, length, options) {
 				throw customError("Circular invocation", 'CIRCULAR_INVOCATION');
 			}
 			cache.data = result;
-			if (setListeners) conf.emit('set', 'data');
+			if (setListeners) conf.emit('set', 'data', null, result);
 			return result;
 		};
 	} else {
@@ -83,7 +83,7 @@ module.exports = function (original, length, options) {
 				throw customError("Circular invocation", 'CIRCULAR_INVOCATION');
 			}
 			cache[id] = result;
-			if (setListeners) conf.emit('set', id);
+			if (setListeners) conf.emit('set', id, null, result);
 			return result;
 		};
 	}

package.json

@@ -34,6 +34,7 @@
     "timers-ext": "0.1"
   },
   "devDependencies": {
+    "plain-promise": "^0.1.1",
     "tad": "~0.2.3",
     "xlint": "~0.2.2",
     "xlint-jslint-medikoo": "~0.1.4"

test/ext/max-age.js

@@ -1,7 +1,8 @@
 'use strict';
 
 var memoize  = require('../..')
-  , nextTick = require('next-tick');
+  , nextTick = require('next-tick')
+  , Promise = global.Promise || require('plain-promise');
 
 require('../../ext/async');
 
@@ -52,6 +53,60 @@ module.exports = function () {
 					}, 90);
 				}, 20);
 			},
+			Promise: function (a, d) {
+				var mfn, fn, i = 0;
+				fn = function (x, y) {
+					return new Promise(function (res) {
+						++i;
+						res(x + y);
+					});
+				};
+
+				mfn = memoize(fn, { promise: true, maxAge: 100 });
+
+				mfn(3, 7).then(function (res) {
+					a(res, 10, "Result #1");
+				});
+				mfn(5, 8).then(function (res) {
+					a(res, 13, "Result #2");
+				});
+				mfn(3, 7).then(function (res) {
+					a(res, 10, "Result #3");
+				});
+				mfn(3, 7).then(function (res) {
+					a(res, 10, "Result #4");
+				});
+				mfn(5, 8).then(function (res) {
+					a(res, 13, "Result #5");
+				});
+
+				setTimeout(function () {
+					a(i, 2, "Called #2");
+
+					mfn(3, 7).then(function (res) {
+						a(res, 10, "Again: Result #1");
+					});
+					mfn(5, 8).then(function (res) {
+						a(res, 13, "Again: Result #2");
+					});
+
+					setTimeout(function () {
+						a(i, 2, "Again Called #2");
+
+						mfn(3, 7).then(function (res) {
+							a(res, 10, "Again: Result #1");
+						});
+						mfn(5, 8).then(function (res) {
+							a(res, 13, "Again: Result #2");
+						});
+
+						nextTick(function () {
+							a(i, 4, "Call After clear");
+							d();
+						});
+					}, 100);
+				}, 20);
+			},
 			Async: function (a, d) {
 				var mfn, fn, u = {}, i = 0;
 				fn = function (x, y, cb) {