checking in docs for github.io page

docs/step2-01/demo/src/generics/index.ts

@@ -0,0 +1,23 @@
+// Generics for classes
+class Stack<T = number> {
+  private data: T[] = [];
+
+  push(item: T) {
+    this.data.push(item);
+  }
+  pop(): T {
+    return this.data.pop();
+  }
+}
+
+const numberStack = new Stack();
+const stringStack = new Stack<string>();
+
+// Generics for functions
+function reverse<T>(arg: T[]): T[] {
+  // TODO: implement the logic to reverse the array
+  return arg;
+}
+
+// adding an export to turn this into a "module"
+export default {};