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📜 WAYPOINT LESSON

Checkpoint: The Heterogeneous Type-Safe Container

⭐⭐⭐ advanced⏳ 25 min read📍 Lesson 144 of 180

Carry types through erasure with Class<T> tokens and type.cast retrieval.

Checkpoint: the heterogeneous type-safe container

Generics are erased — but a Class<T> token is the runtime type. Build the type-safe heterogeneous container: one map, many value types, retrieval that cannot lie about its type. This is the 60-line ancestor of every DI container and JSON binder.