From 0bd85ce30559140bc358b915e0273d4882b2ace3 Mon Sep 17 00:00:00 2001
From: Brendan Chen <me@bchen.dev>
Date: Wed, 29 Jan 2025 16:56:52 -0800
Subject: [PATCH 1/3] add tests for tuple key type

---
 test/types/TupleKeyTests.test.ts | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 test/types/TupleKeyTests.test.ts

diff --git a/test/types/TupleKeyTests.test.ts b/test/types/TupleKeyTests.test.ts
new file mode 100644
index 0000000..f4760ef
--- /dev/null
+++ b/test/types/TupleKeyTests.test.ts
@@ -0,0 +1,18 @@
+import { describe, expect, it } from "@jest/globals";
+import { TupleKey } from "../../src/types/TupleKey";
+
+describe("TupleKey", () => {
+  it("stores a value copy of the original tuple", () => {
+    const tuple: [string, string] = ["150", "539"];
+    const tupleKey = new TupleKey(...tuple);
+
+    expect(tupleKey.tuple).toEqual(tuple);
+  });
+
+  it("returns a string representation of itself", () => {
+    const tuple: [string, string] = ["150", "539"];
+    const tupleKey = new TupleKey(...tuple);
+
+    expect(`${tupleKey}`).toEqual("150|539");
+  });
+});
\ No newline at end of file

From 7de1fd757e164d5f291d2572778a2bfdda190195 Mon Sep 17 00:00:00 2001
From: Brendan Chen <me@bchen.dev>
Date: Wed, 29 Jan 2025 16:57:00 -0800
Subject: [PATCH 2/3] add TupleKey class

---
 src/types/TupleKey.ts | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 src/types/TupleKey.ts

diff --git a/src/types/TupleKey.ts b/src/types/TupleKey.ts
new file mode 100644
index 0000000..08dcfb4
--- /dev/null
+++ b/src/types/TupleKey.ts
@@ -0,0 +1,19 @@
+const separator = "|";
+
+export class TupleKey<T extends any[]> {
+  public readonly tuple: T;
+  private readonly strKey: string;
+
+  constructor(...tuple: T) {
+    this.tuple = tuple;
+    this.strKey = tuple.join(separator);
+  }
+
+  toString(): string {
+    return this.strKey;
+  }
+
+  valueOf(): string {
+    return this.strKey;
+  }
+}

From 6f1464d55a7a860dc7f22a9d1d3eae2c4cc95063 Mon Sep 17 00:00:00 2001
From: Brendan Chen <me@bchen.dev>
Date: Wed, 29 Jan 2025 17:07:35 -0800
Subject: [PATCH 3/3] add test for object as key use case

---
 test/types/TupleKeyTests.test.ts | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/types/TupleKeyTests.test.ts b/test/types/TupleKeyTests.test.ts
index f4760ef..ac260dd 100644
--- a/test/types/TupleKeyTests.test.ts
+++ b/test/types/TupleKeyTests.test.ts
@@ -15,4 +15,17 @@ describe("TupleKey", () => {
 
     expect(`${tupleKey}`).toEqual("150|539");
   });
+
+  it("supports usage as key in object", () => {
+    const tupleKey1 = new TupleKey("1", "2");
+    const tupleKey2 = new TupleKey("3", "4");
+
+    const sampleObject = {
+      [tupleKey1.toString()]: "value1",
+      [tupleKey2.toString()]: "value2",
+    };
+
+    expect(sampleObject[tupleKey1.toString()]).toEqual("value1");
+    expect(sampleObject[(new TupleKey("1", "2")).toString()]).toEqual("value1");
+  });
 });
\ No newline at end of file