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# Left Trim

> Trim whitespace characters from the beginning of a string.

<section class="usage">

## Usage

```javascript
var ltrim = require( '@stdlib/string/left-trim' );
```

#### ltrim( str )

Trims whitespace from the beginning of a `string`.

```javascript
var out = ltrim( ' \r\n\t  Beep \t\t\n  ' );
// returns 'Beep \t\t\n  '
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   Following [Unicode 6.3.0][unicode] and later, "whitespace" is defined as the following characters: `[ \\f\\n\\r\\t\\v\\u0020\\u00a0\\u1680\\u2000-\\u200a\\u2028\\u2029\\u202f\\u205f\\u3000\\ufeff]`.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var ltrim = require( '@stdlib/string/left-trim' );

var str = ltrim( '   Whitespace   ' );
// returns 'Whitespace   '

str = ltrim( '\t\t\tTabs\t\t\t' );
// returns 'Tabs\t\t\t'

str = ltrim( '\n\n\nNew Lines\n\n\n' );
// returns 'New Lines\n\n\n'
```

</section>

<!-- /.examples -->

* * *

<section class="cli">

## CLI

<section class="usage">

### Usage

```text
Usage: ltrim [options] [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --split sep           Delimiter for stdin data. Default: '/\\r?\\n/'.
```

</section>

<!-- /.usage -->

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

<section class="notes">

### Notes

-   If the split separator is a [regular expression][mdn-regexp], ensure that the `split` option is either properly escaped or enclosed in quotes.

    ```bash
    # Not escaped...
    $ echo -n $'   foo   \n   bar   ' | ltrim --split /\r?\n/

    # Escaped...
    $ echo -n $'   foo   \n   bar   ' | ltrim --split /\\r?\\n/
    ```

-   The implementation ignores trailing delimiters.

</section>

<!-- /.notes -->

<section class="examples">

### Examples

```bash
$ ltrim '  beep boop'
beep boop
```

To use as a [standard stream][standard-streams],

```bash
$ echo -n '  beep boop' | ltrim
beep boop
```

By default, when used as a [standard stream][standard-streams], the implementation assumes newline-delimited data. To specify an alternative delimiter, set the `split` option.

```bash
$ echo -n '   foo   \t   bar   \t   baz   ' | ltrim --split '\t'
foo   
bar   
baz   
```

</section>

<!-- /.examples -->

</section>

<!-- /.cli -->

<!-- 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/trim`][@stdlib/string/trim]</span><span class="delimiter">: </span><span class="description">trim whitespace characters from the beginning and end of a string.</span>
-   <span class="package-name">[`@stdlib/string/right-trim`][@stdlib/string/right-trim]</span><span class="delimiter">: </span><span class="description">trim whitespace characters from the end 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="links">

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

[unicode]: https://en.wikipedia.org/wiki/Unicode

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

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

[@stdlib/string/trim]: https://github.com/stdlib-js/string/tree/main/trim

[@stdlib/string/right-trim]: https://github.com/stdlib-js/string/tree/main/right-trim

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

</section>

<!-- /.links -->