\ba Unicode word boundary
\w+a Unicode word character, repeated at least once
:the literal : (5810 / 728 / 3A16)
\s+a Unicode whitespace character, repeated at least once
nullthe literal text null (case sensitive) ,the literal , (4410 / 548 / 2C16)
\s*a Unicode whitespace character, repeated any number of times
$end of string, or before its final line terminator
g modifier: global. Finds all matches instead of stopping after the first