 		Yaku.onUnhandledRejection p._value, p
 		return
 
+	checkRejection = (p) ->
+		pre = p._pre
+		while pre
+			return if pre._hasUnhandled
+
+			pre = pre._pre
+
+		p._hasUnhandled = true
+		scheduleUnhandledRejection p
+
 	callHanler = (handler, value) ->
 		# 2.2.5
 		handler value

		if isFunction onRejected
			p2._onRejected = onRejected

		p2[$prePromise] = p1

		# 2.2.6
		if p1._state == $pending

	$resolved = 1
	$pending = 2

	$promiseStack = '_pStack'

	# These are some symbols. They won't be used to store data.
