Rust for C-Programmers

10.10 Summary

Rust’s enums combine the strengths of C enums and unions in a safer, more expressive form. Their features include:

• Type Safety: No mixing of integers and enum variants.
• Pattern Matching: Concise, clear logic for handling each possibility.
• Data-Carrying Variants: Variants can hold additional data, from simple tuples to complex structs.
• Exhaustiveness: The compiler enforces handling all variants.
• Memory Flexibility: Large data can reside on the stack or be allocated on the heap via Box.
• Seamless Usage: They work smoothly in collections and function parameters.
• Foundation for Option and Result: Core Rust types are built on the same enum semantics.

Enums are integral to idiomatic Rust. Mastering them, along with the pattern matching constructs that support them, will help you write safer, clearer, and more efficient programs. Explore creating your own enums, experiment with pattern matching, and note the differences from concepts like inheritance in other languages. You’ll quickly see how enums simplify many common programming tasks while ensuring correctness in Rust applications.