^start of line
Negative Lookahead(?!none@|na@) none@the literal text none@ (case sensitive) na@the literal text na@ (case sensitive) \w+any word character, repeated at least once
*repeats the group contents below any number of times:
\.the literal . (4610 / 568 / 2E16)
\w+any word character, repeated at least once
@the literal @ (6410 / 1008 / 4016)
+repeats the group contents below at least once:
\w+any word character, repeated at least once
\.the literal . (4610 / 568 / 2E16)
\w{2,4}any word character, repeated between 2 and 4 times
$end of line
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string