Chore: Some todos about matching entities as sequence

geary-core/src/commonMain/kotlin/com/mineinabyss/geary/datatypes/EntityType.kt

@@ -86,8 +86,6 @@ class EntityType private constructor(
         return EntityType(arr)
     }
 
-    //TODO intersection and union
-
     override fun toString(): String =
         inner.joinToString(", ", prefix = "[", postfix = "]") { it.readableString() }
 }

geary-core/src/commonMain/kotlin/com/mineinabyss/geary/engine/QueryManager.kt

@@ -9,5 +9,13 @@ interface QueryManager {
     fun trackEventListener(listener: Listener)
     fun trackQuery(query: GearyQuery)
 
+    /** Returns a list of entities matching the given family. */
     fun getEntitiesMatching(family: Family): List<Entity>
+
+    /**
+     * Returns a sequence of entities matching the given family.
+     * This should be faster than [getEntitiesMatching] but will depend on impl.
+     * In an archetypal engine, this gets all matching archetypes first, then maps them to entities as a sequence.
+     */
+    fun getEntitiesMatchingAsSequence(family: Family): Sequence<Entity>
 }

geary-core/src/commonMain/kotlin/com/mineinabyss/geary/engine/archetypes/ArchetypeQueryManager.kt

@@ -89,10 +89,13 @@ class ArchetypeQueryManager : QueryManager {
         return archetypes.match(family)
     }
 
-    //TODO convert to Sequence
     override fun getEntitiesMatching(family: Family): List<Entity> {
-        return getArchetypesMatching(family).flatMap { arc ->
-            arc.entities
-        }
+        return getArchetypesMatching(family).flatMap(Archetype::entities)
+    }
+
+    override fun getEntitiesMatchingAsSequence(family: Family): Sequence<Entity> {
+        return getArchetypesMatching(family)
+            .asSequence()
+            .flatMap(Archetype::entities)
     }
 }