src/effect/EffectSchemaTraitExpression.ts

@@ -0,0 +1,53 @@
+import { Schema as S } from "@effect/schema"
+import { Simplify } from "type-fest"
+import { Trait, TraitTuple } from "../Trait"
+import { StaticImplements, TraitExpression } from "../TraitExpression"
+import { Extend } from "../util"
+
+
+export class EffectSchemaTraitExpression<
+    Superclass   extends S.Class<unknown, Fields, A, I, R, C, Inherited, Proto>,
+    Fields       extends S.Struct.Fields,
+    A, I, R, C,
+    Inherited    extends object,
+    Proto,
+
+    const Traits extends readonly Trait<any, any, any, any>[],
+> {
+    constructor(
+        readonly superclass:  Superclass,
+        readonly traits:      Traits,
+    ) {}
+
+
+    extends<Self>(): (
+        S.Class<
+            Self,
+            Fields,
+            A, I, R, C,
+            Simplify<
+                Extend<[
+                    Inherited,
+                    ...TraitTuple.MapImplInstance<Traits>
+                ]>
+            >,
+            Proto
+        > &
+
+        Simplify<
+            Extend<TraitTuple.MapImplStaticMembers<Traits>>
+        >
+    ) {
+        return this.traits.reduce(
+            (previous, trait) => trait.apply(previous),
+            this.superclass,
+        ) as any
+    }
+
+
+    staticImplements(_target: StaticImplements<TraitExpression<Superclass, Traits>>, _context: any) {}
+
+    get staticImplementsStage2() {
+        return (_target: StaticImplements<TraitExpression<Superclass, Traits>>) => {}
+    }
+}