[masklinn]

I think an interesting component is that you might also want “semi linear types”: types which are purportedly linear but can be dropped as an unwinding backstop.

For instance if you’re dealing with database transactions you probably want to make it explicit whether you commit or rollback, but on panic you can likely allow the transaction to be cleaned up automatically.

[ameliaquining]

Most Rust ORMs and query builders expose a transaction API that takes a closure and runs it inside the transaction, rolling back on unwind or (in most cases) if it's not explicitly committed. This is the most common idiom in Rust for dealing with situations where you want to pass extra data to or from a cleanup routine. Unfortunately, for the async use case in particular it happens to be unsound: https://tmandry.gitlab.io/blog/posts/2023-03-01-scoped-tasks...