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9. Best Practices, Common Pitfalls & Performance Tuning

Best Practices

  1. Exploit Static Monotonicity: Express upper-bound limitations using non-decreasing monotonic sums (\(S \le C\)) without surrounding them in valid is_closed;. This allows the Rave compiler to classify them as Final Rules, maximizing search space pruning speed.
  2. Isolate Domain Concepts: Avoid mixing structural level logic with financial calculations. Separate legality rules (CONSTRAINT) from objective functions (PROPERTY cost).
  3. Minimize Level Context Transitions: Prefer localized traversers (sum(leg(duty), ...)) over multi-level nested traversers across entire rosters where possible.

Common Pitfalls

  • Misusing valid is_closed; on Final Rules: Wrapping a simple duty flight time rule (sum(leg(duty), leg.%time%) <= 08:00) in valid is_closed; neutralizes its ability to prune incomplete sub-trips, causing massive performance degradation.
  • Temporal Disdependencies: Subtracting times out of chronological order (e.g., start_time - end_time) breaks automatic non-negativity type inference, causing the rule classifier to fall back to unoptimized evaluation.
  • Implicit Universal Traversal: Calling unbounded all() or any() traversers over large rosters inside inner generation loops instead of restricting evaluation to the current active Duty or Trip.