^start of line
Positive Lookahead(?=\D*\d) \D*any character that's not a digit, repeated any number of times
\da digit
.*any character (except for line terminators), repeated any number of times
\Sany non-whitespace character
\$the literal $ (3610 / 448 / 2416)
.*any character (except for line terminators), repeated any number of 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