[Caml-list] Lwt and exceptions (2015)

[Mike Lin <mlin@mlin.net>]

[-- Attachment #1: Type: text/plain, Size: 982 bytes --]

Dear all,
I've long been observing the admonishment to avoid raising native exceptions in Lwt code [1,2]. However, it has not escaped my notice that between Lwt.catch, the try%lwt syntax extension, and the fact that Lwt.bind sets up a handler for native exceptions raised in asynchronous callbacks [3], they're usually handled just as one would naively expect. Actually, I spent a little time trying to come up with a non-terribly-contrived example where using a native exception breaks the intended handling logic, and did not succeed...
Perhaps the situation has evolved over time as some of the aforementioned features have been added to Lwt. Can anyone venture to define precisely when it's wrong to raise native exceptions in Lwt code, as of 2015?
[1] https://mirage.io/wiki/tutorial-lwt[2] http://caml-list.inria.narkive.com/YRIVPWeD/lwt-and-exceptions[3] https://github.com/ocsigen/lwt/blob/bb75e9185e2cf9a71d13b5008d08dae8fdc90f4d/src/core/lwt.ml#L653
Mike
 		 	   		  

[-- Attachment #2: Type: text/html, Size: 1341 bytes --]