[Twisted-Python] Some things I've learned: safer callbacks, better t.p.context

Not been doing much Twisted lately, but have been doing async stuff elsewhere, and I've learned some useful things. 1. Callbacks should be sync or async, but never sometimes-one-sometimes-the-other. For details go read http://blog.ometer.com/2011/07/24/callbacks-synchronous-and-asynchronous/. For example, Deferred.addCallback(f) really should never run f() immediately. 3. By instrumenting all callbacks it manages, which may or may not require item #1, Twisted can have a context that automatically follows callbacks. Node has this and it is extremely useful. http://fredkschott.com/post/2014/02/conquering-asynchronous-context-with-cls... is best summary I've found with a bit of searching. -- Itamar Turner-Trauring