1/*! ***************************************************************************** 2Copyright (c) Microsoft Corporation. All rights reserved. 3Licensed under the Apache License, Version 2.0 (the "License"); you may not use 4this file except in compliance with the License. You may obtain a copy of the 5License at http://www.apache.org/licenses/LICENSE-2.0 6 7THIS CODE IS PROVIDED ON AN *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 8KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED 9WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE, 10MERCHANTABLITY OR NON-INFRINGEMENT. 11 12See the Apache Version 2.0 License for specific language governing permissions 13and limitations under the License. 14***************************************************************************** */ 15 16 17 18/// <reference no-default-lib="true"/> 19 20 21interface String { 22 /** 23 * Returns a new String consisting of the single UTF-16 code unit located at the specified index. 24 * @param index The zero-based index of the desired code unit. A negative index will count back from the last item. 25 */ 26 at(index: number): string | undefined; 27} 28