feat: add reverse

README.md

@@ -160,6 +160,7 @@ type res5 = Pipe<
   - [x] `Filter<Fn, Tuple>`
   - [x] `Reduce<Fn, Init, Tuple>`
   - [x] `ReduceRight<Fn, Init, Tuple>`
+  - [x] `Reverse<Tuple>`
   - [x] `Every<Fn, Tuple>`
   - [x] `Some<Fn, Tuple>`
   - [x] `ToUnion<Tuple>`

src/internals/tuples/Tuples.ts

@@ -260,6 +260,26 @@ export namespace Tuples {
     return: ReduceImpl<Extract<this["arg0"], Fn>, this["arg1"], this["arg2"]>;
   }
 
+  type ReverseImpl<tuple> = tuple extends [infer first, ...infer rest]
+    ? [...ReverseImpl<rest>, first]
+    : [];
+
+  /**
+   * Reverse a tuple.
+   * @params args[0] - A tuple.
+   * @return Reversed tuple.
+   * @example
+   * ```ts
+   * type T0 = Call<T.Reverse,[1,2,3]>; // [3,2,1]
+   * ```
+   */
+  export type Reverse<tuple extends readonly any[] | unset = unset> =
+    PartialApply<ReverseFn, [tuple]>;
+
+  interface ReverseFn extends Fn {
+    return: ReverseImpl<this["arg0"]>;
+  }
+
   type ReduceRightImpl<xs, acc, fn extends Fn> = xs extends [
     ...infer rest,
     infer last

test/tuples.test.ts

@@ -148,6 +148,12 @@ describe("Tuples", () => {
     type tes3 = Expect<Equal<res3, "b">>;
   });
 
+  it("Reverse", () => {
+    type res1 = Call<Tuples.Reverse, ["a", "b", "c", 2, "d"]>;
+    //   ^?
+    type tes1 = Expect<Equal<res1, ["d", 2, "c", "b", "a"]>>;
+  });
+
   it("Drop", () => {
     type res1 = Call<Tuples.Drop<1>, ["a", "b", "c", 2, "d"]>;
     //   ^?