1/* 2 * Copyright (c) 2024 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/*--- 17 desc: 10.04.Interface_Members 18 name: 10.Interfaces/10.04.Interface_Members/interface_with_optional_attributes_0002.sts 19 tags: 20 ---*/ 21 22class Teacher { 23 name: string; 24 25 constructor(name: string) { 26 this.name = name; 27 } 28} 29 30interface IStudent { 31 name: string; 32 age: int; 33 desc: string; 34 teacher?: Teacher | undefined 35} 36 37class Student implements IStudent { 38 name: string; 39 age: int; 40 desc: string; 41 teacher?: Teacher | undefined 42 43 constructor(name: string, age: int, desc: string, teacher: Teacher) { 44 this.name = name; 45 this.age = age; 46 this.desc = desc 47 this.teacher = teacher 48 } 49 50 constructor(name: string, age: int, desc: string) { 51 this.name = name; 52 this.age = age; 53 this.desc = desc 54 } 55} 56 57function main() : void { 58 let s : Student = new Student("Klara", 18, "an excellent student", new Teacher("Anna")); 59 let s1 : Student = new Student("Karl", 18, "a bad student"); 60 61 assert s.name == "Klara" 62 assert s.age == 18 63 assert s.desc == "an excellent student" 64 assert s.teacher?.name == "Anna" 65 assert s1.name == "Karl" 66 assert s1.age == 18; 67 assert s1.desc == "a bad student"; 68 assert s1.teacher?.name == undefined; 69} 70