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_ciinterface Z { 173af6ab5fSopenharmony_ci foo: number; 183af6ab5fSopenharmony_ci} 193af6ab5fSopenharmony_ci 203af6ab5fSopenharmony_ciinterface Z1 { 213af6ab5fSopenharmony_ci bar: string; 223af6ab5fSopenharmony_ci} 233af6ab5fSopenharmony_ci 243af6ab5fSopenharmony_ci // X implements interface Z, which makes relation between X and Y explicit. 253af6ab5fSopenharmony_ci class C implements Z, Z1 { 263af6ab5fSopenharmony_ci public foo: number 273af6ab5fSopenharmony_ci public bar: string; 283af6ab5fSopenharmony_ci 293af6ab5fSopenharmony_ci constructor() { 303af6ab5fSopenharmony_ci this.foo = 0 313af6ab5fSopenharmony_ci this.bar = "Class C"; 323af6ab5fSopenharmony_ci } 333af6ab5fSopenharmony_ci } 343af6ab5fSopenharmony_ci 353af6ab5fSopenharmony_ci // Y implements interface Z, which makes relation between X and Y explicit. 363af6ab5fSopenharmony_ci class C2 implements Z, Z1 { 373af6ab5fSopenharmony_ci public foo: number; 383af6ab5fSopenharmony_ci public bar: string; 393af6ab5fSopenharmony_ci 403af6ab5fSopenharmony_ci constructor() { 413af6ab5fSopenharmony_ci this.foo = 0; 423af6ab5fSopenharmony_ci this.bar = "Class C2"; 433af6ab5fSopenharmony_ci } 443af6ab5fSopenharmony_ci } 453af6ab5fSopenharmony_ci 463af6ab5fSopenharmony_ci let x1: Z = new C() 473af6ab5fSopenharmony_ci let y1: Z1 = new C2() 483af6ab5fSopenharmony_ci 493af6ab5fSopenharmony_ciconsole.log("Assign X to Y") 503af6ab5fSopenharmony_ciy1 = x1 // ok, both are of the same type 513af6ab5fSopenharmony_ci 523af6ab5fSopenharmony_ciconsole.log("Assign Y to X") 533af6ab5fSopenharmony_cix1 = y1 // ok, both are of the same type 54