Object pools

When there are some big objects, or even non-encodable objects in the Rust side, you may not want (or impossible) to copy them between Rust and Dart over and over again.

Opaque Rust types

This is, by default, handled via opaque Rust types, and there is no operation needed to take care of the scenario.

(Legacy) Real object pools

However, for legacy reasons (flutter_rust_bridge V1) and for completeness, here we also document an alternative solution (object pool): By using object pools, you only pass around a "object handle" (just a few integers) between Rust and Dart, and the Rust side will convert that handle from and to the real object. For installation, please refer to cancelable tasks.