src/abstract.ts

@@ -5,6 +5,6 @@ export type AbstractTag = "@thilawyn/traitify-ts/Abstract"
 
 export function abstract<
     Abstract extends {} = {}
->(): Opaque<Abstract, AbstractTag> {
-    return undefined as any
+>() {
+    return {} as Opaque<Abstract, AbstractTag>
 }

src/trait.ts

@@ -28,17 +28,27 @@ type RemoveAbstractFromImpl<
 
 
 export class Trait<
-    Abstract extends {},
-    Impl     extends Class<{}, []>,
+    Abstract    extends {},
+    Impl        extends Class<{}, []>,
+    Supertraits extends Trait<any, any, any>[]
 > {
     constructor(
-        readonly abstract:  Abstract,
-        readonly apply:     (Super: AbstractClass<{}>) => Impl,
+        readonly supertraits:  Supertraits,
+        readonly ownAbstract:  Abstract,
+        readonly apply:        (Super: AbstractClass<{}>) => Impl,
     ) {}
 }
 
+export interface Trait<
+    Abstract    extends {},
+    Impl        extends Class<{}, []>,
+    Supertraits extends Trait<any, any, any>[]
+> {
+    get ownImplClass(): Impl
+}
+
 export type TraitAbstractMembers<T> = (
-    T extends Trait<infer AbstractMembers, any>
+    T extends Trait<infer AbstractMembers, any, any>
         ? AbstractMembers
         : never
 )
@@ -48,7 +58,7 @@ export interface TraitAbstractMembersFn extends Fn {
 }
 
 export type TraitImplClass<T> = (
-    T extends Trait<any, infer Impl>
+    T extends Trait<any, infer Impl, any>
         ? Impl
         : never
 )
@@ -102,6 +112,7 @@ export function trait<
     ),
 ) {
     return new Trait(
+        []       as const,
         abstract as Abstract,
         apply    as any as (Super: AbstractClass<{}>) => RemoveAbstractFromImpl<ImplWithAbstract, Abstract>,
     )