13af6ab5fSopenharmony_ci/*
23af6ab5fSopenharmony_ci * Copyright (c) 2024 Huawei Device Co., Ltd.
33af6ab5fSopenharmony_ci * Licensed under the Apache License, Version 2.0 (the "License");
43af6ab5fSopenharmony_ci * you may not use this file except in compliance with the License.
53af6ab5fSopenharmony_ci * You may obtain a copy of the License at
63af6ab5fSopenharmony_ci *
73af6ab5fSopenharmony_ci * http://www.apache.org/licenses/LICENSE-2.0
83af6ab5fSopenharmony_ci *
93af6ab5fSopenharmony_ci * Unless required by applicable law or agreed to in writing, software
103af6ab5fSopenharmony_ci * distributed under the License is distributed on an "AS IS" BASIS,
113af6ab5fSopenharmony_ci * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
123af6ab5fSopenharmony_ci * See the License for the specific language governing permissions and
133af6ab5fSopenharmony_ci * limitations under the License.
143af6ab5fSopenharmony_ci */
153af6ab5fSopenharmony_ci
163af6ab5fSopenharmony_ciclass A {
173af6ab5fSopenharmony_ci    data: string[] = ['a', 'b', 'c'];
183af6ab5fSopenharmony_ci    $_iterator() {
193af6ab5fSopenharmony_ci      return new DIterator(this);
203af6ab5fSopenharmony_ci    }
213af6ab5fSopenharmony_ci}
223af6ab5fSopenharmony_ci
233af6ab5fSopenharmony_ciclass CIterator implements Iterator<string> {
243af6ab5fSopenharmony_ci    index = 0;
253af6ab5fSopenharmony_ci    base: A;
263af6ab5fSopenharmony_ci    constructor (base: A) {
273af6ab5fSopenharmony_ci        this.base = base;
283af6ab5fSopenharmony_ci    }
293af6ab5fSopenharmony_ci    next(): IteratorResult<string> {
303af6ab5fSopenharmony_ci        if (this.index >= this.base.data.length) {
313af6ab5fSopenharmony_ci            return {
323af6ab5fSopenharmony_ci                done: true,
333af6ab5fSopenharmony_ci                value: undefined
343af6ab5fSopenharmony_ci            }
353af6ab5fSopenharmony_ci        }
363af6ab5fSopenharmony_ci        return {
373af6ab5fSopenharmony_ci          done: this.index >= this.base.data.length,
383af6ab5fSopenharmony_ci          value: this.base.data[this.index++]
393af6ab5fSopenharmony_ci        }
403af6ab5fSopenharmony_ci    }
413af6ab5fSopenharmony_ci}
423af6ab5fSopenharmony_ci
433af6ab5fSopenharmony_ciclass DIterator extends CIterator {
443af6ab5fSopenharmony_ci    constructor (base: A) {
453af6ab5fSopenharmony_ci            super(base);
463af6ab5fSopenharmony_ci        }
473af6ab5fSopenharmony_ci}
483af6ab5fSopenharmony_ci
493af6ab5fSopenharmony_cifunction main(): void {
503af6ab5fSopenharmony_ci    let res = "";
513af6ab5fSopenharmony_ci    let a = new A();
523af6ab5fSopenharmony_ci    for (let x of a) res += x;
533af6ab5fSopenharmony_ci    assert(res == "abc");
543af6ab5fSopenharmony_ci}
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