npm package: @stdlib/string-first
Description: Return the first character(s) of a string.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
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  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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</details>

# first

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Return the first character(s) of a string.

<section class="installation">

## Installation

```bash
npm install @stdlib/string-first
```

</section>

<section class="usage">

## Usage

```javascript
var first = require( '@stdlib/string-first' );
```

#### first( str\[, n]\[, options] )

Returns the first character(s) of a string.

```javascript
var out = first( 'last man standing' );
// returns 'l'

out = first( 'Hidden Treasures' );
// returns 'H'
```

The function supports the following options:

-   **mode**: type of characters to return. Must be one of the following:

    -   `'grapheme'`: grapheme clusters. Appropriate for strings containing visual characters which can span multiple Unicode code points (e.g., emoji).
    -   `'code_point'`: Unicode code points. Appropriate for strings containing visual characters which are comprised of more than one Unicode code unit (e.g., ideographic symbols and punctuation and mathematical alphanumerics).
    -   `'code_unit'`: UTF-16 code units. Appropriate for strings containing visual characters drawn from the basic multilingual plane (BMP) (e.g., common characters, such as those from the Latin, Greek, and Cyrillic alphabets).

    Default: `'grapheme'`.

By default, the function returns the first character. To return the first `n` characters, provide a second argument specifying the number of characters to return.

```javascript
var out = first( 'foo bar', 5 );
// returns 'foo b'

out = first( 'foo bar', 10 );
// returns 'foo bar'
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   By default, the function assumes the general case in which an input string may contain an arbitrary number of grapheme clusters. This assumption comes with a performance cost. Accordingly, if an input string is known to only contain visual characters of a particular type (e.g., only alphanumeric), one can achieve better performance by specifying the appropriate `mode` option.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var first = require( '@stdlib/string-first' );

var str = first( 'last man standing' );
// returns 'l'

str = first( 'presidential election' );
// returns 'p'

str = first( 'javaScript' );
// returns 'j'

str = first( 'Hidden Treasures' );
// returns 'H'

str = first( 'The Last of the Mohicans', 5 );
// returns 'The L'

str = first( '🐶🐮🐷🐰🐸', 2 );
// returns '🐶🐮'

str = first( '🐶🐮🐷🐰🐸', 10 );
// returns '🐶🐮🐷🐰🐸'
```

</section>

<!-- /.examples -->



<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

## See Also

-   <span class="package-name">[`@stdlib/string-first-cli`][@stdlib/string-first-cli]</span><span class="delimiter">: </span><span class="description">CLI package for use as a command-line utility.</span>
-   <span class="package-name">[`@stdlib/string-remove-first`][@stdlib/string/remove-first]</span><span class="delimiter">: </span><span class="description">remove the first character(s) of a string.</span>
-   <span class="package-name">[`@stdlib/string-last`][@stdlib/string/last]</span><span class="delimiter">: </span><span class="description">return the last character(s) of a string.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->


<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

<!-- /.stdlib -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[@stdlib/string-first-cli]: https://www.npmjs.com/package/@stdlib/string-first-cli

[npm-image]: http://img.shields.io/npm/v/@stdlib/string-first.svg
[npm-url]: https://npmjs.org/package/@stdlib/string-first

[test-image]: https://github.com/stdlib-js/string-first/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/string-first/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/string-first/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/string-first?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

[cli-section]: https://github.com/stdlib-js/string-first#cli
[cli-url]: https://github.com/stdlib-js/string-first/tree/cli
[@stdlib/string-first]: https://github.com/stdlib-js/string-first/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/string-first/tree/deno
[deno-readme]: https://github.com/stdlib-js/string-first/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/string-first/tree/umd
[umd-readme]: https://github.com/stdlib-js/string-first/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/string-first/tree/esm
[esm-readme]: https://github.com/stdlib-js/string-first/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/string-first/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/string-first/main/LICENSE

[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams

[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions

<!-- <related-links> -->

[@stdlib/string/remove-first]: https://www.npmjs.com/package/@stdlib/string-remove-first

[@stdlib/string/last]: https://www.npmjs.com/package/@stdlib/string-last

<!-- </related-links> -->

</section>

<!-- /.links -->