domenic
commented
10 years ago I think this has been sufficiently accomplished as of fe8194a3967d78863cbd0ad25f7ad0afc4918167. Any further formalization would need to be done at the WebIDL level, and is tracked as https://www.w3.org/Bugs/Public/show_bug.cgi?id=26103
This is actually really important. Ties into issues around what "run to completion" means. Things like, what is an "asynchronously run" set of steps allowed to do? Only non-observable things, like queuing and task, or resolving a promise. This is actually a constant danger with potential data races around every corner.
We think that the style in this guide (as opposed to "return and continue running the following steps") is probably better for guiding toward the right path and avoiding those dangers. But note that it isn't intrinsically better.