Question: How to return something that borrows from the function context? about neon

[demurgos]

After you return the value it is managed by the JS VM. The result must be 'static. If RowIter borrows from something, it is not compatible and you need to refactor your code to avoid this non-static lifetime.

You could maybe consider moving the connection with the stream using some of the crates enabling self-referential structs.

[kjvalencik]

The issue is that repo is borrowing from repo_wrapper. When a value is put in a JsBox, ownership is transferred to the JavaScript runtime and you can only get references afterwards.

The typical pattern in Rust for this is to wrap the value in an Arc.

[stevenliebregt]

As far as I see I can't make this work with Neon, I tried looking at the gzip-stream example, but that uses Clone which I can't use as the underlying connection also isn't cloneable.

[kjvalencik]

That's what reference counting like an Arc does. It makes it cloneable (cloning increments the counter instead of copying the struct).

[stevenliebregt]

I feel like I'm not clear enough on what my problem exactly is, but I have a hard time explaining it.

The Repo has a postgres::Client and has a method fn query_many_stream(&mut self) -> Result<postgres::RowIter, Error> this RowIter has a lifetime 'a to the connection.

I have a hard time seeing what part exactly I should wrap in a Mutex, any help is much appreciated.