Comment by at_compile_time

On the contrary, I find indices to be the most natural way to represent anything that resembles a graph in Rust. They allow you to sidestep the usual issues that arise with ownership and borrowing, particularly with mutability, by handing ownership to the collection and using indices to allow nodes to refer to one another. It's delightfully simple compared to the mess of Arc and RefCell that tends to result when one tries to apply patterns from languages that leave "shared XOR mutable" as the programmer's responsibility. That's not to say that Vec and usize are appropriate for the task, but Rust's type system can be used to do a lot better.