# truncateMiddle
> Truncate a string in the middle to a specified length.
## Usage
```javascript
var truncateMiddle = require( '@stdlib/string/truncate-middle' );
```
#### truncate( str, len\[, seq] )
Truncates a string in the middle to a specified length.
```javascript
var out = truncateMiddle( 'beep boop', 7 );
// returns 'be...op'
```
By default, the truncated string uses the replacement sequence `'...'`. To customize the replacement sequence, provide a `seq` argument:
```javascript
var out = truncateMiddle( 'beep boop', 7, '!' );
// returns 'bee!oop'
out = truncateMiddle( 'beep boop', 7, '!!!' );
// returns 'be!!!op'
```
## Examples
```javascript
var truncateMiddle = require( '@stdlib/string/truncate-middle' );
var str = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.';
var out = truncateMiddle( str, 15 );
// returns 'Lorem ... elit.'
str = 'To be or not to be, that is the question';
out = truncateMiddle( str, 19, '|' );
// returns 'To be or | question'
str = 'The quick fox jumps over the lazy dog.';
out = truncateMiddle( str, 28, '...' );
// returns 'The quick fox...he lazy dog.'
str = '🐺 Wolf Brothers 🐺';
out = truncateMiddle( str, 7 );
// returns '🐺 ... 🐺'
str = '🐺 Wolf Pack 🐺';
out = truncateMiddle( str, 7, '🐺🐺🐺' );
// returns '🐺 🐺🐺🐺 🐺'
```
* * *
## CLI
### Usage
```text
Usage: truncate-middle [options] [] --len
Options:
-h, --help Print this message.
-V, --version Print the package version.
--len length String length.
--seq str Custom replacement sequence. Default: '...'.
--split sep Delimiter for stdin data. Default: '/\\r?\\n/'.
```
### 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 $'Hello, World!\nBeep Boop Baz' | truncate-middle --len 6 --split /\r?\n/
# Escaped...
$ echo -n $'Hello, World!\nBeep Boop Baz' | truncate-middle --len 6 --split /\\r?\\n/
```
- The implementation ignores trailing delimiters.
### Examples
```bash
$ truncate-middle 'Hello, World!' --len 8
Hel...d!
$ truncate-middle 'Hello, World!' --len 6 --seq '!'
Hel|d!
```
To use as a [standard stream][standard-streams],
```bash
$ echo -n 'Hello, World!' | truncate-middle --len 8
Hel...d!
```
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 'Hello, World!\tBeep Boop' | truncate-middle --split '\t' --len 6 --seq '!'
Hel|d!
Bee|op
```
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
[mdn-regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
[@stdlib/string/truncate]: https://github.com/stdlib-js/string/tree/main/truncate