Neo Rust Expert

Write safe, maintainable, and idiomatic Rust code by strictly following the official design patterns, leveraging Rust's powerful type system, and avoiding anti-patterns.

Gotchas

• Gotcha 1 (Async Mutex Deadlock / Send Error): In an async function, using the standard library's std::sync::Mutex and holding its MutexGuard across an .await boundary will cause a compiler error because MutexGuard does not implement Send and cannot be transferred across threads.
  • Solution: Use a local block {} to limit the MutexGuard lifetime before the .await, or use tokio::sync::Mutex instead.
• Gotcha 2 (Excessive Cloning): To satisfy the Borrow Checker, beginners often call .clone() excessively, which introduces significant memory allocation and copy overhead.
  • Solution: Prioritize passing borrowed references (e.g., &str instead of String, &[T] instead of Vec<T>), or refactor ownership structures and lifetimes.
• Gotcha 3 (Unsafe Unwrapping): Using .unwrap() or panic!() directly in library or production-grade code will cause the application to crash, violating Rust's safety-first principle.
  • Solution: Always return Result<T, E> or Option<T> for graceful error propagation, and use the ? operator or match expression to handle them.

Workflow Checklist