Test if a position in a string marks the start of a UTF-16 surrogate pair.
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> Test if a position in a string marks the start of a [UTF-16][utf-16] surrogate pair.
``bash`
npm install @stdlib/assert-has-utf16-surrogate-pair-at
`javascript`
var hasUTF16SurrogatePairAt = require( '@stdlib/assert-has-utf16-surrogate-pair-at' );
#### hasUTF16SurrogatePairAt( string, position )
Tests if a position (in [UTF-16][utf-16] code units) in a string marks the start of a [UTF-16][utf-16] surrogate pair.
`javascript
var bool = hasUTF16SurrogatePairAt( '🌷', 0 );
// returns true
bool = hasUTF16SurrogatePairAt( '🌷', 1 );
// returns false
`
- Note that position does not refer to a visual character position, but to an index in the ordered sequence of [UTF-16][utf-16] code units.
`javascript
var hasUTF16SurrogatePairAt = require( '@stdlib/assert-has-utf16-surrogate-pair-at' );
var bool = hasUTF16SurrogatePairAt( '🌷', 0 );
// returns true
bool = hasUTF16SurrogatePairAt( '🌷', 1 );
// returns false
`
- [@stdlib/assert-has-utf16-surrogate-pair-at-cli][@stdlib/assert-has-utf16-surrogate-pair-at-cli]: CLI package for use as a command-line utility.
*
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---
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[cli-section]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at#cli
[cli-url]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/tree/cli
[@stdlib/assert-has-utf16-surrogate-pair-at]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/tree/main
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-has-utf16-surrogate-pair-at/blob/esm/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-has-utf16-surrogate-pair-at/main/LICENSE
[utf-16]: https://en.wikipedia.org/wiki/UTF-16
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams