Rust Borrow Checker

1. Each value has exactly one owner - When the owner goes out of scope, the value is dropped
2. You can have either one mutable reference OR any number of immutable references - Never both simultaneously
3. References must always be valid - No dangling references, lifetimes must be sufficient

Understanding these rules is the key to fixing borrow checker errors.

1. Diagnose a borrow checker error (paste the error)
2. Fix a lifetime annotation issue
3. Fix an ownership transfer problem
4. Fix a mutable/immutable borrow conflict
5. Understand a specific error code

Paste the compiler error or describe the issue, then I'll route to the appropriate workflow.

E0382 (use of moved value): Clone, use references, or restructure to avoid the move E0502 (cannot borrow as mutable, already borrowed as immutable): Separate the borrows into different scopes, or use interior mutability (RefCell, Mutex) E0499 (cannot borrow as mutable more than once): Split into separate scopes or use indices instead of references E0597 (borrowed value does not live long enough): Extend the lifetime of the owner, or use owned types instead E0506 (cannot assign, already borrowed): Complete borrow before assignment, or use Cell/RefCell

Core Rules:

• ownership-rules.md - The three ownership rules with examples
• borrowing-rules.md - Borrowing and reference rules
• lifetime-syntax.md - Lifetime annotation patterns and elision

Problem Solving:

• common-errors.md - Detailed breakdown of E0XXX errors
• patterns.md - Clone, Rc, Arc, RefCell, Cow patterns