^start of line
Group 1(\d{1,3}(?:\.\d{1,3}){3}) \d{1,3}a digit, repeated between 1 and 3 times
Non-Capturing Group(?:\.\d{1,3}){3} {3}repeats the group contents below exactly 3 times:
\.the literal . (4610 / 568 / 2E16)
\d{1,3}a digit, repeated between 1 and 3 times
\s*any whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
\s*any whitespace character, repeated any number of times
(?1)calls group 1 as a subroutine
\s*any whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
\s*any whitespace character, repeated any number of times
Group 3((?:[0-9A-Fa-f]{2}[:-]){3,6}[0-9A-Fa-f]{2}) Non-Capturing Group(?:[0-9A-Fa-f]{2}[:-]){3,6} {3,6}repeats the group contents below between 3 and 6 times:
Character Class[0-9A-Fa-f]{2} {2}matches exactly 2 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
A-Fone character from A (6510) to F (7010) (case sensitive)
a-fone character from a (9710) to f (10210) (case sensitive)
:the literal : (5810 / 728 / 3A16)
-the literal - (4510 / 558 / 2D16)
Character Class[0-9A-Fa-f]{2} {2}matches exactly 2 characters from the set below:
0-9one character from 0 (4810) to 9 (5710)
A-Fone character from A (6510) to F (7010) (case sensitive)
a-fone character from a (9710) to f (10210) (case sensitive)
\s*any whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
\s*any whitespace character, repeated any number of times
Group 4(\d\d/\d\d/\d{4}\s\d\d(?::\d\d){2}|NEVER EXPIRES|INACTIVE) 1st Alternative\d\d/\d\d/\d{4}\s\d\d(?::\d\d){2} \da digit
\da digit
/the literal / (4710 / 578 / 2F16)
\da digit
\da digit
/the literal / (4710 / 578 / 2F16)
\d{4}a digit, repeated exactly 4 times
\sany whitespace character
\da digit
\da digit
Non-Capturing Group(?::\d\d){2} {2}repeats the group contents below exactly 2 times:
:the literal : (5810 / 728 / 3A16)
\da digit
\da digit
2nd AlternativeNEVER EXPIRES NEVER EXPIRESthe literal text NEVER EXPIRES (case sensitive) INACTIVEthe literal text INACTIVE (case sensitive) \s*any whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
\s*any whitespace character, repeated any number of times
\s*any whitespace character, repeated any number of times
-the literal - (4510 / 558 / 2D16)
\s*any whitespace character, repeated any number of times
.*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