src/trait-inheritance.ts

@@ -1,4 +1,4 @@
-import { AbstractClass, Opaque, UnionToIntersection } from "type-fest"
+import { AbstractClass, AbstractConstructor, Opaque, UnionToIntersection } from "type-fest"
 
 
 /**
@@ -11,24 +11,29 @@ export type StaticMembers<C> = Pick<C, keyof C>
 
 
 export type Trait<
-    C extends AbstractClass<any, any>
+    C extends AbstractClass<any>
 > = Opaque<
-    (Parent: AbstractClass<any, any[]>) => C,
-    "Trait"
+    TraitApplier<C>,
+    "thilatrait/Trait"
 >
 
-export type GetTraitC<T> =
+export type TraitApplier<
+    C extends AbstractClass<any>
+> =
+    (Parent: AbstractConstructor<any>) => C
+
+export type UnwrapTraitC<T> =
     T extends Trait<infer C>
         ? C
         : never
 
 
 export function trait<
-    C extends AbstractClass<any, any[]>
+    C extends AbstractClass<any>
 >(
-    trait: (Parent: AbstractClass<any, any[]>) => C
+    applier: TraitApplier<C>
 ) {
-    return trait as Trait<C>
+    return applier as Trait<C>
 }
 
 
@@ -48,7 +53,7 @@ export function extendsAndExpresses<
             InstanceType<C> &
             UnionToIntersection<
                 InstanceType<
-                    GetTraitC<
+                    UnwrapTraitC<
                         Traits[number]
                     >
                 >
@@ -60,7 +65,7 @@ export function extendsAndExpresses<
         StaticMembers<C> &
         StaticMembers<
             UnionToIntersection<
-                GetTraitC<
+                UnwrapTraitC<
                     Traits[number]
                 >
             >