make_clickable

Source code

function make_clickable($ret) {

	$ret = ' ' . $ret;

	// in testing, using arrays here was found to be faster

	$save = @ini_set('pcre.recursion_limit', 10000);

	$retval = preg_replace_callback('#(?<!=[\'"])(?<=[*\')+.,;:!&$\s>])(\()?([\w]+?://(?:[\w\\x80-\\xff\#%~/?@\[\]-]{1,2000}|[\'*(+.,;:!=&$](?![\b\)]|(\))?([\s]|$))|(?(1)\)(?![\s<.,;:]|$)|\)))+)#is', '_make_url_clickable_cb', $ret);

	if (null !== $retval )

		$ret = $retval;

	@ini_set('pcre.recursion_limit', $save);

	$ret = preg_replace_callback('#([\s>])((www|ftp)\.[\w\\x80-\\xff\#$%&~/.\-;:=,?@\[\]+]+)#is', '_make_web_ftp_clickable_cb', $ret);

	$ret = preg_replace_callback('#([\s>])([.0-9a-z_+-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})#i', '_make_email_clickable_cb', $ret);

	// this one is not in an array because we need it to run last, for cleanup of accidental links within links

	$ret = preg_replace("#(<a( [^>]+?>|>))<a [^>]+?>([^>]+?)</a></a>#i", "$1$3</a>", $ret);

	$ret = trim($ret);

	return $ret;

}