Re: [RFC] Context Managers

On Tue, Nov 4, 2025, at 21:13, Larry Garfield wrote: > Arnaud and I would like to present another RFC for consideration: Context Managers. > > https://wiki.php.net/rfc/context-managers > > You'll probably note that is very similar to the recent proposal from Tim and Seifeddine. > Both proposals grew out of casual discussion several months ago; I don't believe either team > was aware that the other was also actively working on such a proposal, so we now have two. > C'est la vie. :-) > > Naturally, Arnaud and I feel that our approach is the better one. In particular, as Arnaud > noted in an earlier reply, __destruct() is unreliable if timing matters. It also does not allow > differentiating between a success or failure exit condition, which for many use cases is absolutely > mandatory (as shown in the examples in the context manager RFC). > > The Context Manager proposal is a near direct port of Python's approach, which is > generally very well thought-out. However, there are a few open questions as listed in the RFC that > we are seeking feedback on. > > Discuss. :-) > > -- > Larry Garfield > larry@garfieldtech.com > Hi Larry/Arnaud, This is a pretty exciting thread and fascinating proposal. That being said, I have a couple of subtle questions that don't seem to be answered in the (very long) thread or the RFC itself -- If I missed it, please let me know: 1. What happens if a Fiber is suspended in the using block and never resumed? When is the using block released to clean up the context? 2. There's still no mention of how this should affect debugging, will we see the "desugared" or "sugared" version? Is that even a concern for the RFC? 3. I will say it is weird to have exitContext return an exception; but what happens if an exception is thrown during exitContext? Why not just have it return void and throw if you need to throw instead of having two paths to the same thing? 4. Looking at the desugared form ... I'm a bit confused: if exitContext is called during the finally path and returns an exception, it is just swallowed? But if it is thrown, it won't be? 5. That being said, I don't think the RFC shares with us when we should return an exception vs. throw an exception. — Rob