>Why a Total Order, Not a DAG?

>This is a deliberate design decision. lock_tree uses a DAG, which lets you declare that branches A and B are independent — neither needs to come before the other. Sounds great, but it has a subtle problem: if thread 1 acquires A then B, and thread 2 acquires B then A, and both orderings are valid in the DAG, you have a deadlock that the compiler happily approved.

Would it be possible to build one at compile time? Static levels seem like they won't let you share code without level-collaboration, so that might be kinda important for larger-scale use.

I don't know enough about Rust's type system to know if that's possible though. Feels like it's pushing into "maybe" territory, like maybe not with just linear types but what about proc macros?

I can definitely see why it's easier to build this way though, and for some contexts that limitation seems entirely fine. Neat library, and nice post :)