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function is not described

_make_url_clickable_cb() WP 2.3.2

Callback to convert URI match to HTML A element.

This function was backported from 2.5.0 to 2.3.2. Regex callback for make_clickable().

No Hooks.

Return

String. HTML A element with URI address.

Usage

_make_url_clickable_cb( $matches );
$matches(array) (required)
Single Regex Match.

Code of make url clickable cb: wp-includes/formatting.php VER 5.0.3

<?php
function _make_url_clickable_cb( $matches ) {
	$url = $matches[2];

	if ( ')' == $matches[3] && strpos( $url, '(' ) ) {
		// If the trailing character is a closing parethesis, and the URL has an opening parenthesis in it, add the closing parenthesis to the URL.
		// Then we can let the parenthesis balancer do its thing below.
		$url .= $matches[3];
		$suffix = '';
	} else {
		$suffix = $matches[3];
	}

	// Include parentheses in the URL only if paired
	while ( substr_count( $url, '(' ) < substr_count( $url, ')' ) ) {
		$suffix = strrchr( $url, ')' ) . $suffix;
		$url = substr( $url, 0, strrpos( $url, ')' ) );
	}

	$url = esc_url($url);
	if ( empty($url) )
		return $matches[0];

	return $matches[1] . "<a href=\"$url\" rel=\"nofollow\">$url</a>" . $suffix;
}