@stdlib/string/remove-last/README.md

String manipulation functions.

<!--

@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.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

-->

# removeLast

> Remove the last character(s) of a string.

<section class="usage">

## Usage

```javascript
var removeLast = require( '@stdlib/string/remove-last' );
```

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

Removes the last character(s) of an input string.

```javascript
var out = removeLast( 'last man standing' );
// returns 'last man standin'

out = removeLast( 'Hidden Treasures' );
// returns 'Hidden Treasure'
```

The function supports the following options:

-   **mode**: type of characters to remove. 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 last character. To return the last `n` characters, provide a second argument specifying the number of characters to return.

```javascript
var out = removeLast( 'foo bar', 4 );
// returns 'foo'

out = removeLast( 'foo bar', 0 );
// 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 removeLast = require( '@stdlib/string/remove-last' );

var str = removeLast( 'last man standing' );
// returns 'last man standin'

str = removeLast( 'presidential election' );
// returns 'presidential electio'

str = removeLast( 'javaScript' );
// returns 'javaScrip'

str = removeLast( 'Hidden Treasures' );
// returns 'Hidden Treasure'

str = removeLast( 'Lorem ipsum dolor sit amet', 4 );
// returns 'Lorem ipsum dolor sit '

str = removeLast( '🐮🐷🐸🐵', 2 );
// returns '🐮🐷'
```

</section>

<!-- /.examples -->

* * *

<section class="cli">

## CLI

<section class="usage">

### Usage

```text
Usage: remove-last [options] [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --n                   Number of characters to remove. Default: 1.
         --split sep           Delimiter for stdin data. Default: '/\\r?\\n/'.
         --mode mode           Type of character to remove. Default: 'grapheme'.
```

</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 $'beep\nboop' | remove-last --split /\r?\n/

    # Escaped...
    $ echo -n $'beep\nboop' | remove-last --split /\\r?\\n/
    ```

-   The implementation ignores trailing delimiters.

</section>

<!-- /.notes -->

<section class="examples">

### Examples

```bash
$ remove-last beep
bee
```

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

```bash
$ echo -n 'beep\nboop' | remove-last --n 2
be
bo
```

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 'beep\tboop' | remove-last --split '\t'
bee
boo
```

</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/remove-first`][@stdlib/string/remove-first]</span><span class="delimiter">: </span><span class="description">remove the first 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="links">

[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://github.com/stdlib-js/string/tree/main/remove-first

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

</section>

<!-- /.links -->