@stdlib/regexp/eol/README.md

Regular expressions.

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# reEOL

> [Regular expression][mdn-regexp] to match a [newline][newline] character sequence.

<section class="usage">

## Usage

```javascript
var reEOL = require( '@stdlib/regexp/eol' );
```

#### reEOL( \[options] )

Returns a [Regular expression][mdn-regexp] to match a [newline][newline] character sequence. 

```javascript
var RE_EOL = reEOL();

var bool = RE_EOL.test( '\n' );
// returns true

bool = RE_EOL.test( '\r\n' );
// returns true

bool = RE_EOL.test( '\\r\\n' );
// returns false
```

The function accepts an `options` object with optional properties:

-   **flags**: `string` specifying regular expression [flags][mdn-regexp-flags]. Default: `''`.
-   **capture**: `boolean` indicating whether to create a capture group for the match. Default: `false`.

By default, the function returns a regular expression which does not have any flags specified. To specify [flags][mdn-regexp-flags], set the `flags` option with a list of flags (which may be in any order).

```javascript
var replace = require( '@stdlib/string/replace' );

var RE_EOL = reEOL({
    'flags': 'g'
});

var str = '1\n2\n3';
var out = replace( str, RE_EOL, '' );
// returns '123'
```

By default, the function returns a regular expression which does not capture the part of a string matching the regular expression. To capture matches, set the `capture` option.

```javascript
var RE_EOL = reEOL({
    'capture': true
});

var str = 'beep\nboop';
var arr = str.split( RE_EOL );
// returns [ 'beep', '\n', 'boop' ]
```

#### reEOL.REGEXP

[Regular expression][mdn-regexp] to match a [newline][newline] character sequence. 

```javascript
var bool = reEOL.REGEXP.test( 'abc' );
// returns false
```

#### reEOL.REGEXP_CAPTURE

[Regular expression][mdn-regexp] to capture a [newline][newline] character sequence. 

```javascript
var parts = reEOL.REGEXP_CAPTURE.exec( '\n' );
// returns [ '\n', '\n' ]
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

```javascript
var reEOL = require( '@stdlib/regexp/eol' );

var RE_EOL = reEOL();
var bool;
var str;

bool = RE_EOL.test( '\r\n' );
// returns true

bool = RE_EOL.test( '\n' );
// returns true

bool = RE_EOL.test( '\r' );
// returns false

bool = RE_EOL.test( '\\r\\n' );
// returns false

bool = RE_EOL.test( 'beep' );
// returns false

str = 'This is\na newline\r\ndelimited string.';

var arr = str.split( RE_EOL );
// returns [ 'This is', 'a newline', 'delimited string.' ]
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</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">

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

[mdn-regexp-flags]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions#advanced_searching_with_flags_2

[newline]: https://en.wikipedia.org/wiki/Newline

</section>

<!-- /.links -->