wp_spaces_regexp() │ WP 4.0.0

Returns the regexp for common whitespace characters.

By default, spaces include new lines, tabs, nbsp entities, and the UTF-8 nbsp. This is designed to replace the PCRE \s sequence. In ticket #22692, that sequence was found to be unreliable due to random inclusion of the A0 byte.

1 time — 0.000001 sec (speed of light) | 50000 times — 0.000001 sec (speed of light) | PHP 7.3.12, WP 5.3.2

Hooks from the function

wp_spaces_regexp

Return

String. The spaces regexp.

Usage

wp_spaces_regexp();

Examples

#1 Example of using the function

An example of a regular expression using the wp_spaces_regexp() function.

$spaces = wp_spaces_regexp(); // string(25) "[\r\n\t ]|\xC2\xA0| "

var_dump($spaces);

$text = "  \t  footer";
$pattern = "(?:{$spaces})*foo"; // possible starting spaces

echo preg_replace( "/$pattern/", '', $text );
// outputs "ter"

Changelog

Since 4.0.0

Introduced.

Code of `wp_spaces_regexp() wp spaces regexp` ^{WP 6.0}

wp-includes/formatting.php

function wp_spaces_regexp() {
	static $spaces = '';

	if ( empty( $spaces ) ) {
		/**
		 * Filters the regexp for common whitespace characters.
		 *
		 * This string is substituted for the \s sequence as needed in regular
		 * expressions. For websites not written in English, different characters
		 * may represent whitespace. For websites not encoded in UTF-8, the 0xC2 0xA0
		 * sequence may not be in use.
		 *
		 * @since 4.0.0
		 *
		 * @param string $spaces Regexp pattern for matching common whitespace characters.
		 */
		$spaces = apply_filters( 'wp_spaces_regexp', '[\r\n\t ]|\xC2\xA0|&nbsp;' );
	}

	return $spaces;
}