$re = '/\.([A-Za-z]+)\s*(?==)(?=.*\b\1\b.*).*/m';
$str = 'global.second = second
global.minute = minute
global.respect = respect
global.Respect = Respect
respect.count = You have # ${global.respect}
give.respect = Get more ${global.respect} by giving others respect.
give.Respect = Get more ${global.Respect} by giving others Respect.
give.Respect = Get more ${global.Respect} by giving others respect.
give.Respect = Get more ${global.count} by giving others count.
give.Respect = Get more ${global.Respect} by giving others count.';
preg_match_all($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