m05-type-driven

Compile-time invariants in Rust are enforced using type-driven design techniques like type-state patterns, newtypes, and marker traits to prevent invalid states. This approach guarantees correctness by shifting validation to the compiler.

The type-state pattern in Rust encodes state machines directly into the type system to guard state transitions at compile time. By using PhantomData and marker traits, it ensures only valid state transitions are permitted.

A safe builder pattern in Rust uses marker traits and type-state encoding to ensure only valid object constructions compile successfully. This guarantees that required fields and invariants are satisfied before instantiation.

Type-driven design is preferred over runtime validation in Rust when you need to eliminate runtime errors for domain invariants and state machines. It provides safer APIs with zero runtime costs by checking validity during compilation.

PhantomData and newtype wrappers enforce domain invariants in Rust without runtime overhead by encoding rules directly into the type system. This allows the compiler to reject invalid states during compilation.

Type-state patterns in Rust can increase code complexity and boilerplate when modeling highly complex state machines with many transitions. It is best suited for production-grade designs where compile-time safety outweighs structural verbosity.