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 16abstract class C{ 17 field1?:number; 18 field2?:string; 19} 20 21function main(){ 22 let x:C = {field1:1000,field2:"some str"} 23 assertEQ(x.field1, 1000) 24 assertEQ(x.field2, "some str") 25 26 let x2:C = {field2:"some str"} 27 assertEQ(x2.field1, undefined) 28 assertEQ(x2.field2, "some str") 29 30 let x3:C = {} 31 assertEQ(x3.field1, undefined) 32 assertEQ(x3.field2, undefined) 33} 34