1/* 2 * Copyright (c) 2025 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16interface A { 17 callback: Object; 18} 19 20class B { 21 foo(): void { }; 22} 23 24class C implements A { 25 private b?: B; 26 constructor(b: B) { 27 this.b = b; 28 } 29 public callback: Object = (c: String): String => { 30 this.b?.foo(); 31 return c; 32 } 33} 34 35function main() { 36 let b = new B(); 37 let temp = new C(b); 38 const s = (temp.callback as (c: String) => String)("hello"); 39 assertEQ(s, "hello"); 40} 41