$text = $some_str || ''

Please note that the defined-or operator is //, not ||. $text = $some_str || '' silently converts 0 to the empty string due to boolean evaluation of $some_str, causing even more subtile bugs.

The defined-or operator was introduced in perl v5.10. For older perl versions, you need to use something like $text=defined($some_str) ? $some_str : ''.

Alexander