~
<url>\s*
(?>
(?>
(?><lastmod>\s*(?<mod>[^<]+)\s*</lastmod>)
|
(?><changefreq>\s*(?<freq>\w+)\s*</changefreq>)
|
(?><priority>\s*(?<prio>[01](?>\.\d{1,2})?)\s*</priority>)
)\s*
){0,3}\s*
<loc>\s*
(?<uri>[^<]+)\s*
</loc>\s*
(?>
(?>
(?><lastmod>\s*(?<mod>[^<]+)\s*</lastmod>)
|
(?><changefreq>\s*(?<freq>\w+)\s*</changefreq>)
|
(?><priority>\s*(?<prio>[01](?>\.\d{1,2})?)\s*</priority>)