[utility.requirements,exception.propagation] Clarify the thrown exceptions that have requirements and guarantees imposed LWG3640

[JohelEGP]

Resolves #4863.

[tkoeppe]

I would like some LWG input on both this PR and the underlying issue.

[JohelEGP]

It seems to me that some select cwg-labeled issues reach CWG's plate, but that such is not the case for lwg. Should I submit a LWG issue, or is there some process behind these labels?

[tkoeppe]

@JohelEGP: If you're unsure if something is editorial, then it's definitely more reliable to start with an LWG issue, and LWG can decide that it's editorial. Otherwise I'll do my best to get LWG's attention, but that process is not terribly reliable. Generally, the less certain I am that something is obviously editorial, the less I'm willing to make changes unilaterally and will try to get some expert input.

CWG has a different work load and has been able to review editorial issues from GitHub reguarly recently, but fundamentally the same applies there, too: if something isn't obviously editorial, it's safer to go via the issues lists. We'll do our best here, but just in case you're looking for hard guarantees.

[JohelEGP]

Thank you. I will consider submitting a LWG issue soon.

We'll do our best here, but just in case you're looking for hard guarantees.

I certainly wouldn't like this to go stale. The same might apply to others who have their issues labeled. Do you think that information is fit for the wiki? Or perhaps just being more clear as to how the WG's input should come about: you contacting them (perhaps with no hard guarantees) or the issues' author submitting an issue.

[tkoeppe]

Maybe? We already say, "If you are not sure whether your proposed edit falls into the above categories, you should consider submitting it as a technical issue instead.", but we could add that we'll try our best to triage and redirect, but without guarantees?

[JohelEGP]

Well, it's been a long time since I've read that. I suppose it's already clear enough.

[jensmaurer]

If you do get an LWG issue number, please let us know in a comment.

[jensmaurer]

It is not obvious to me that we want to go in this direction, or whether we prefer fixing the individual descriptions to talk about "initialization" and "assignment" more directly instead of choosing wording that allows to ignore some areas of the full-expression under discussion.

[JohelEGP]

This is now https://wg21.link/LWG3640.