feat[ptr]: 通过 generator API 实现迭代器模式

Author: ceilf6

Design-Pattern/Behavioral/Iterator/generatorEx/Client.ts

@@ -0,0 +1,42 @@
+type Book = {
+    id: number;
+    title: string;
+};
+
+class BookCollection {
+    private readonly books: Book[] = [];
+
+    add(book: Book): void {
+        this.books.push(book);
+    }
+
+    // function*
+    // Generator 作为具体迭代器：按顺序逐个产出集合元素
+    *createIterator(): Generator<Book, void, unknown> {
+        for (const book of this.books) {
+            yield book;
+        }
+    }
+}
+
+function runDemo(): void {
+    const collection = new BookCollection();
+    collection.add({ id: 1, title: "Design Patterns" });
+    collection.add({ id: 2, title: "Refactoring" });
+    collection.add({ id: 3, title: "Clean Code" });
+
+    console.log("--- 手动 next() 遍历 ---");
+    const iterator = collection.createIterator();
+    let result = iterator.next();
+    while (!result.done) { // 迭代器对象还没有 done
+        console.log(result.value);
+        result = iterator.next();
+    }
+
+    console.log("--- for...of 遍历 ---");
+    for (const book of collection.createIterator()) {
+        console.log(`${book.id}. ${book.title}`);
+    }
+}
+
+runDemo();