time-to-botec/squiggle/node_modules/@stdlib/string/left-trim/README.md

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@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.
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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 -->