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

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@license Apache-2.0
Copyright (c) 2021 The Stdlib Authors.
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# rtrimN
> Trim `n` characters from the end of a string.
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## Usage
```javascript
var rtrimN = require( '@stdlib/string/right-trim-n' );
```
#### rtrimN( str, n\[, chars] )
Trims `n` characters from the end of a string.
```javascript
var str = ' foo ';
var out = rtrimN( str, str.length );
// returns ' foo'
out = rtrimN( str, 1 );
// returns ' foo '
```
By default, the function trims whitespace characters. To trim a different set of characters instead, provide a string or an array of characters to trim:
```javascript
var str = '🐶🐶🐶 Animals 🐶🐶🐶';
var out = rtrimN( str, str.length, [ '🐶', ' ' ] );
// returns '🐶🐶🐶 Animals'
out = rtrimN( str, str.length, '🐶 ' );
// returns '🐶🐶🐶 Animals'
```
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## Examples
<!-- eslint no-undef: "error" -->
```javascript
var rtrimN = require( '@stdlib/string/right-trim-n' );
var out = rtrimN( ' Whitespace ', 3 );
// returns ' Whitespace'
out = rtrimN( '\t\t\tTabs\t\t\t', 2 );
// returns '\t\t\tTabs\t'
out = rtrimN( '~~~CUSTOM~~~', 3, '~' );
// returns '~~~CUSTOM'
```
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* * *
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## CLI
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### Usage
```text
Usage: rtrimn [options] --n=<number>
Options:
-h, --help Print this message.
-V, --version Print the package version.
--n number Number of characters to trim.
--chars str Characters to trim. Default: whitespace.
--split sep Delimiter for stdin data. Default: '/\\r?\\n/'.
```
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### 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 ' | rtrimn --n=3 --split /\r?\n/
# Escaped...
$ echo -n $' foo \n bar ' | rtrimn --n=3 --split /\\r?\\n/
```
- The implementation ignores trailing delimiters.
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### Examples
```bash
$ rtrimn ' Whitespace ' --n=3
Whitespace
```
To use as a [standard stream][standard-streams],
```bash
$ echo -n '~beep~boop~~~' | rtrimn --n=2 --chars '~'
~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~~~' | rtrimn --split '\t' --chars '~' --n=3
~~~foo
~~~bar
~~~baz
```
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[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
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