ModifyKind does not derive Copy

[jasonheath]

Apologies if I should ask this in a different place but I think the issues section is correct for this project. I've noticed that ModifyKind doesn't derive Copy. Based on a quick visual inspection I believe that all of its peer enums and the enums it makes use of derive Copy. Is there a reason it doesn't? If there isn't I can submit a pull request that derives copy.

[0xpr03]

Yeah there is currently no real blocker for deriving copy on top of clone. But it also will make it impossible to remove, if for any reason we should want a bigger sub type / value later on. But I could be too restrictive in favor of unknown unknowns.

Is there a good use case for making it copy ?

[dfaust]

Is there a good use case for making it copy ?

When matching on ModifyKind, it is moved into the match and so the event cannot be used anymore.
I believe it should be Copy just like the other enums, so that this use case is easier and the API is more uniform.

[0xpr03]

I would suggest matching over &event. Still, I would merge a PR for this.