Comment by spullara

It is hard for me to fathom the negative feelings towards Promises. They are quite clearly a great way to perform async programming in a civilized way (see Twitter's Future/Promise in Finagle on github). JDK 8 will even have the equivalent in CompletableFuture. The only thing better is to combine Promises with coroutines for a more linear programming style like in Flow: http://www.foundationdb.com/white-papers/flow/