Clever Workaround for Conflicting Blanket Implementations in Rust

Rust's trait system is powerful but strict about avoiding ambiguity in blanket implementations. The author encountered this while building Joydb, needing to support two mutually exclusive implementations of the `Adapter` trait: `UnifiedAdapter` and `PartitionedAdapter`. A direct approach using blanket implementations failed. The solution, detailed in this post, uses marker structs (`Unified` and `Partitioned`), a helper trait (`BlanketAdapter`), and an associated type within the `Adapter` trait. This cleverly allows for both behaviors without violating Rust's coherence rules, maintaining good code ergonomics and maintainability.