| name | rust |
| description | when working on a Rust project |
Before committing any changes in a Rust project
- Run
cargo fmt to format all code
- Verify it succeeds before staging files
- NEVER ever install rustup or run rustup command
When writing code
When a function accepts a byte index representing a character position, assume
the index is aligned to a UTF-8 character boundary.
No magic sentinel values
Never encode "invalid" or "absent" state by stuffing a sentinel number (e.g.
-1) into a field that normally holds real data. This is a common slope AI
pattern and it is broken by design: sentinels are invisible to downstream code
- clamps, casts, arithmetic, and comparisons all treat them as ordinary
values, creating hidden coupling between producer and every consumer. Use
Option<T> or a dedicated enum variant instead.
