[rtpg]

> It's easy to call low-restriction functions from high-restriction ones and not the other way around.

do you have an example in mind when you say this? I think there's some unique messes with async/await (especially when combined with OOP and extension points... either your extension points _all_ have to be async or you have to have awkward restrictions), in a way that, say, permission checks don't have IMO.

a syntax-less "await function" that climbs up the stack trace to whoever is waiting and holds onto the suspension _is_ a way out of the problem the article describes. Requires runtime support but it effectively means you can always suspend.