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function is not described

_links_add_base() WP 2.7.0

Callback to add a base url to relative links in passed content.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

String. The processed link.

Usage

_links_add_base( $m );
$m(string) (required)
The matched link.

Notes

  • Global. String. $_links_add_base

Changelog

Since 2.7.0 Introduced.

Code of _links_add_base() WP 5.7.2

<?php
function _links_add_base( $m ) {
	global $_links_add_base;
	// 1 = attribute name  2 = quotation mark  3 = URL.
	return $m[1] . '=' . $m[2] .
		( preg_match( '#^(\w{1,20}):#', $m[3], $protocol ) && in_array( $protocol[1], wp_allowed_protocols(), true ) ?
			$m[3] :
			WP_Http::make_absolute_url( $m[3], $_links_add_base )
		)
		. $m[2];
}