$re = '/^{{\s?(?:\:{1,2}|!){1}\s?([a-zA-z0-9\.]+)\s?(?:\|\s?(\w+))?\s?}}$/m';
$str = '{{ :: campaign_statuses.send }}
{{::campaign_statuses.send}}
{{ :: campaign_statuses.send | number }}
{{::campaign_statuses.send|number}}
{{ ! 123123123 | number }}
{{!123123123|number}}
{{ !>>::campaign.date_created | 123123123 | number }}
{{!>>::campaign.date_created123123123|number}}
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php