replace RelationExtensions.GetAllEntityRelations() -> EntityRelation<…

…TRelation>().Pairs

src/ECS/Relations/EntityRelation.cs

@@ -13,7 +13,7 @@ internal EntityRelation(AbstractEntityRelations relations) {
     }
 
     /// <summary>
-    /// Returns a collection of entities having one or more relations of the specified <typeparamref name="TRelation"/> type.<br/>
+    /// Returns a collection of entities having one or more relation.<br/>
     /// Executes in O(1).
     /// </summary>
     /// <remarks>
@@ -23,15 +23,21 @@ internal EntityRelation(AbstractEntityRelations relations) {
     ///   </item>
     ///   <item>
     ///     To get all entities including their relations (the cartesian product aka CROSS JOIN) use<br/>
-    ///     <see cref="RelationExtensions.GetAllEntityRelations{TRelation}"/>
+    ///     <see cref="EntityRelation{TRelation}.Pairs"/>
     ///   </item>
     /// </list>
     /// </remarks>
     public EntityReadOnlyCollection Entities => new EntityReadOnlyCollection(relations.store, relations.positionMap.Keys);
 
     /// <summary>
-    /// Iterates all entity relations of the specified <typeparamref name="TRelation"/> type.<br/>
+    /// Iterates all entity relations.<br/>
     /// Executes in O(N) N: number of all entity relations.
     /// </summary>
     public void For(ForEachEntity<TRelation> lambda) => relations.ForAllEntityRelations(lambda);
+
+    /// <summary>
+    /// Return all entity relations as pairs. A pair is <c>(entities[i], relations[i])</c><br/>
+    /// Executes in O(1).  Most efficient way to iterate all entity relations.
+    /// </summary>
+    public (Entities entities, Chunk<TRelation> relations) Pairs => relations.GetAllEntityRelations<TRelation>();
 }

src/ECS/Relations/RelationExtensions.cs

@@ -121,7 +121,7 @@ public static EntityRelation<TRelation> EntityRelation<TRelation>(this EntitySto
     ///   </item>
     ///   <item>
     ///     To get all entities including their relations (the cartesian product aka CROSS JOIN) use<br/>
-    ///     <see cref="GetAllEntityRelations{TRelation}"/>
+    ///     <see cref="EntityRelation{TRelation}.Pairs"/>
     ///   </item>
     /// </list>
     /// </remarks>
@@ -147,9 +147,11 @@ public static void ForAllEntityRelations<TRelation>(this EntityStore store, ForE
     }
 
     /// <summary>
+    /// Obsolete: Use <see cref="EntityRelation{TRelation}.Pairs"/><br/> 
     /// Return all entity relations  of the specified <typeparamref name="TRelation"/> type.<br/>
     /// Executes in O(1).  Most efficient way to iterate all entity relations.
     /// </summary>
+    [Obsolete("replace with property: EntityRelation<TRelation>().Pairs")]
     public static (Entities entities, Chunk<TRelation> relations) GetAllEntityRelations<TRelation>(this EntityStore store)
         where TRelation : struct, IRelation
     {

src/Tests/ECS/Relations/Test_Relations_Delete.cs

@@ -39,7 +39,7 @@ public static void Test_Relations_Delete_int_relations()
         AreEqual(3, count);
 
         // --- version: get all entity relations in O(1)
-        var (entities, relations) = store.GetAllEntityRelations<IntRelation>();
+        var (entities, relations) = store.EntityRelation<IntRelation>().Pairs;
         AreEqual("{ 1, 1, 2 }",     entities.Debug());
         AreEqual("{ 10, 20, 30 }",  relations.Debug());
 
@@ -86,7 +86,7 @@ public static void Test_Relations_Delete_Entity_relations()
         AreEqual(3, count);
 
         // --- version: get all entity relations in O(1)
-        var (entities, relations) = store.GetAllEntityRelations<AttackRelation>();
+        var (entities, relations) = store.EntityRelation<AttackRelation>().Pairs;
         AreEqual("{ 1, 1, 2 }",     entities.Debug());
         AreEqual("{ 10, 11, 12 }",  relations.Debug());
 

src/Tests/ECS/Relations/Test_Relations_Query.cs

@@ -222,7 +222,7 @@ public static void Test_Relations_GetAllEntityRelations_Perf()
         int count = 0;
         var sw = new Stopwatch();
         sw.Start();
-        var (entities, relations) = store.GetAllEntityRelations<IntRelation>();
+        var (entities, relations) = store.EntityRelation<IntRelation>().Pairs;
         int length = entities.Count;
         for (int n = 0; n < length; n++) {
             count++;