<!-- @license Apache-2.0 Copyright (c) 2018 The Stdlib Authors. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> # UTF-16 Unpaired Surrogate > [Regular expression][mdn-regexp] to match an unpaired [UTF-16][utf-16] surrogate. <section class="usage"> ## Usage <!-- eslint-disable id-length --> ```javascript var reUtf16UnpairedSurrogate = require( '@stdlib/regexp/utf16-unpaired-surrogate' ); ``` #### reUtf16UnpairedSurrogate() Returns a [regular expression][mdn-regexp] to match an unpaired [UTF-16][utf-16] surrogate. <!-- eslint-disable id-length --> ```javascript var RE_UTF16_UNPAIRED_SURROGATE = reUtf16UnpairedSurrogate(); var bool = RE_UTF16_UNPAIRED_SURROGATE.test( 'abc\uD800def' ); // returns true ``` #### reUtf16UnpairedSurrogate.REGEXP [Regular expression][mdn-regexp] to match an unpaired [UTF-16][utf-16] surrogate. ```javascript var bool = reUtf16UnpairedSurrogate.REGEXP.test( 'abc\uD800def' ); // returns true ``` </section> <!-- /.usage --> <section class="examples"> ## Examples <!-- eslint-disable id-length --> <!-- eslint no-undef: "error" --> ```javascript var reUtf16UnpairedSurrogate = require( '@stdlib/regexp/utf16-unpaired-surrogate' ); var RE_UTF16_UNPAIRED_SURROGATE = reUtf16UnpairedSurrogate(); var bool = RE_UTF16_UNPAIRED_SURROGATE.test( '\uD800' ); // returns true bool = RE_UTF16_UNPAIRED_SURROGATE.test( '\uDC00' ); // returns true bool = RE_UTF16_UNPAIRED_SURROGATE.test( 'abc' ); // returns false ``` </section> <!-- /.examples --> <section class="links"> [mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions [utf-16]: https://en.wikipedia.org/wiki/UTF-16 </section> <!-- /.links -->