jcorpac Rust Error Excellence
Rust treats errors as values, not exceptions. This skill ensures your errors provide maximum context for developers and users.
The Result<T, E> Pattern
Always return Result for functions that can fail. Use the ? operator to propagate errors up the stack.
Crate Selection
anyhow: Best for applications. It provides a flexible, easy-to-use error type for top-level handling.thiserror: Best for libraries. It allows you to define custom, derive-based error enums that users can match against.
Best Practices
- Context: Use
.with_context(|| ...)in Anyhow to add human-readable breadcrumbs to errors. - Avoid Panics: Use
unwrap()andexpect()ONLY in tests or when you can prove an invariant is impossible to break. - Custom Errors: Define domain-specific error enums for complex logic.