has_boarding_policy
Use it like this:
- [ #has/_boarding_policy :: BoardingPolicyType ] or
- [ has_boarding_policy :: BoardingPolicyType ]
The type of boarding policy used by the airline (e.g. zone-based or group-based).
Relation describes that: [ #has_/domain :: Airline, Flight ] ( #has_/name :: has_boarding_policy ) ( #has_/range :: BoardingPolicyType )