src/generic/all.ts

@@ -0,0 +1,10 @@
+import { ForType } from '../core/Dispatcher.js'
+import { GenericReturn } from './type.js'
+import * as generic from './arithmetic.js'
+
+export { generic }
+
+declare module "../core/Dispatcher" {
+   interface ReturnTypes<Params>
+      extends ForType<'numbers', GenericReturn<Params>> { }
+}

src/generic/arithmetic.ts

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+import { ConservativeUnary, Dependency, ImpType, Signature } from "../core/Dispatcher";
+
+declare module "./type" {
+  interface GenericReturn<Params> {
+    // Jos: not sure how to define this or why it is needed
+    square: Signature<Params, [T], T>
+    // square: ConservativeUnary<Params, T>
+    // square: Params extends [infer R]
+    //   ? R extends number ? UnderlyingReal<R> : never
+    //    : never
+  }
+}
+
+export const square =
+  <T>(dep: Dependency<'multiply', [T, T]>):
+    ImpType<'square', [T]> =>
+    z => dep.multiply(z, z)

src/generic/type.ts

@@ -0,0 +1,3 @@
+export interface GenericReturn<Params> {
+
+}