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 16 interface Z {} 17 abstract class X<T> { 18 abstract foo(x: string, z?: T) 19 } 20 21 class Y extends X<Z> { 22 foo(x: string, z?: Z) {} 23 } 24 25 let x: X<Z> = new Y() 26 x.foo("Mama!") 27