1/* 2* Copyright (c) Microsoft Corporation. All rights reserved. 3* Copyright (c) 2023 Huawei Device Co., Ltd. 4* Licensed under the Apache License, Version 2.0 (the "License"); 5* you may not use this file except in compliance with the License. 6* You may obtain a copy of the License at 7* 8* http://www.apache.org/licenses/LICENSE-2.0 9* 10* Unless required by applicable law or agreed to in writing, software 11* distributed under the License is distributed on an "AS IS" BASIS, 12* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13* See the License for the specific language governing permissions and 14* limitations under the License. 15* 16* This file has been modified by Huawei to verify type inference by adding verification statements. 17*/ 18 19// === tests/cases/compiler/selfReferencingTypeReferenceInference.ts === 20declare function AssertType(value:any, type:string):void; 21 22interface Box<T> { 23 __: T 24} 25 26type Recursive<T> = 27 | T 28 | Box<Recursive<T>> 29 30type InferRecursive<T> = T extends Recursive<infer R> ? R : "never!" 31 32// the type we are testing with 33type t1 = Box<string | Box<number | boolean>> 34 35type t2 = InferRecursive<t1> 36type t3 = InferRecursive<Box<string | Box<number | boolean>>> // write t1 explicitly 37 38 // Why is t2 and t3 different?? 39 // They have same input type! 40 41