def appended_source
import bendvy-ecs-core@0.1.0.3/relation_graph.bend as RelationGraphimport Base
import entity_key.bend as K
80def appended_source(present: Bool,sources: List<&2,K.Key>,source: K.Key) -> List<&2,K.Key>:
81 match present:
82 case True{}: sources
83 case False{}: List.append(&2,K.Key,sources,[source])