Accept error tuples in emit

[benwilson512]

[benwilson512]

Thoughts @LostKobrakai ?

[LostKobrakai]

I generally like it. The typespec would need updating though.

Also I'd skip the arity-1 callback option. If we introduce the new version of ecto Repo.transaction does pass the repo to both multi and functions passed in. So I'd go for fn aggregate, repo -> or fn aggregate, repo, changes ->. I feel this is nearer to ecto, where at least for multi usage repo is also passed all the time.

[benwilson512]

That's fair, can you elaborate on use of changes? I'm not sure I see when it would be used.

[LostKobrakai]

It‘s the changes provided by Ecto.Multi.run and ….merge.