add simplified aspect builder syntax

src/EcsAspect.cs

@@ -46,6 +46,19 @@ namespace DCFApixels.DragonECS
             private EcsWorld _world;
             private EcsMask.Builder _maskBuilder;
 
+            public IncludeMarker Inc
+            {
+                get { return new IncludeMarker(this); }
+            }
+            public ExcludeMarker Exc
+            {
+                get { return new ExcludeMarker(this); }
+            }
+            public OptionalMarker Opt
+            {
+                get { return new OptionalMarker(this); }
+            }
+
             public EcsWorld World => _world;
 
             private Builder(EcsWorld world)
@@ -406,4 +419,43 @@ namespace DCFApixels.DragonECS
         }
         #endregion
     }
+    public readonly ref struct IncludeMarker
+    {
+        private readonly EcsAspect.Builder _builder;
+        public IncludeMarker(EcsAspect.Builder builder)
+        {
+            _builder = builder;
+        }
+        public T GetInstance<T>() 
+            where T : IEcsPoolImplementation, new()
+        {
+            return _builder.IncludePool<T>();
+        }
+    }
+    public readonly ref struct ExcludeMarker
+    {
+        private readonly EcsAspect.Builder _builder;
+        public ExcludeMarker(EcsAspect.Builder builder)
+        {
+            _builder = builder;
+        }
+        public T GetInstance<T>()
+            where T : IEcsPoolImplementation, new()
+        {
+            return _builder.ExcludePool<T>();
+        }
+    }
+    public readonly ref struct OptionalMarker
+    {
+        private readonly EcsAspect.Builder _builder;
+        public OptionalMarker(EcsAspect.Builder builder)
+        {
+            _builder = builder;
+        }
+        public T GetInstance<T>()
+            where T : IEcsPoolImplementation, new()
+        {
+            return _builder.OptionalPool<T>();
+        }
+    }
 }

src/Pools/EcsPool.cs

@@ -248,6 +248,12 @@ namespace DCFApixels.DragonECS
         IEnumerator<T> IEnumerable<T>.GetEnumerator() { throw new NotImplementedException(); }
         IEnumerator IEnumerable.GetEnumerator() { throw new NotImplementedException(); }
         #endregion
+
+        #region MarkersConverter
+        public static implicit operator EcsPool<T>(IncludeMarker a) { return a.GetInstance<EcsPool<T>>(); }
+        public static implicit operator EcsPool<T>(ExcludeMarker a) { return a.GetInstance<EcsPool<T>>(); }
+        public static implicit operator EcsPool<T>(OptionalMarker a) { return a.GetInstance<EcsPool<T>>(); }
+        #endregion
     }
     /// <summary>Standard component</summary>
     public interface IEcsComponent { }

src/Pools/EcsTagPool.cs

@@ -229,6 +229,12 @@ namespace DCFApixels.DragonECS
         IEnumerator<T> IEnumerable<T>.GetEnumerator() => throw new NotImplementedException();
         IEnumerator IEnumerable.GetEnumerator() => throw new NotImplementedException();
         #endregion
+
+        #region MarkersConverter
+        public static implicit operator EcsTagPool<T>(IncludeMarker a) { return a.GetInstance<EcsTagPool<T>>(); }
+        public static implicit operator EcsTagPool<T>(ExcludeMarker a) { return a.GetInstance<EcsTagPool<T>>(); }
+        public static implicit operator EcsTagPool<T>(OptionalMarker a) { return a.GetInstance<EcsTagPool<T>>(); }
+        #endregion
     }
 
     /// <summary>Component without data</summary>