data-structure

To avoid Rust lifetime issues in compiler data structures, store typed indices instead of direct references. This approach enables mutation without borrow conflicts and guarantees validity by obtaining indices from collection operations like push or enumerate_idx.

The best way to manage contiguous child ranges in a Rust AST arena is using Span. Span provides range semantics that point into a shared arena, keeping parent structs compact and often Copy instead of allocating per-parent Vecs.

Implement safe index-based collections by declaring compact typed indices with newtype_index and using IndexVec. Never manually construct indices; obtain them from collection operations to guarantee type safety and prevent invalid index usage.

You should avoid storing direct references because they cause Rust lifetime complexity and fragile linking. Storing typed indices instead enables safe mutation without borrow conflicts and ensures long-term structural integrity across interlinked collections.

Common anti-patterns include using plain Vec when elements are referenced by index, mixing raw usize across collections, storing long-term references, and constructing indices by hand. These practices lead to invalid indices and fragile code.

Yes, you can use DenseIndexSet for bitset membership operations in a Rust compiler. It provides type-safe membership tracking when combined with typed indices and plank_core utilities, preventing invalid index construction.