Regular Expressions 101

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/
^.*access-list([^\s]*\s){1}(?<src_acl>[^\s]+)\s([^\s]*\s){2}(?<src_iface>[a-z]+)\/(?<src_ip>[0-9.]+)\((?<src_port>[0-9]+)\)\s->\s(?<dest_iface>[a-z]+)\/(?<dest_ip>[0-9.]+)\((?<dest_port>[0-9]+)
/
^ asserts position at start of the string
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
access-list
matches the characters access-list literally (case sensitive)
1st Capturing Group
([^\s]*\s){1}
{1} matches the previous token exactly one time (meaningless quantifier)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character not present in the list below
[^\s]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
Named Capture Group src_acl
(?<src_acl>[^\s]+)
Match a single character not present in the list below
[^\s]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
3rd Capturing Group
([^\s]*\s){2}
{2} matches the previous token exactly 2 times
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character not present in the list below
[^\s]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
Named Capture Group src_iface
(?<src_iface>[a-z]+)
Match a single character present in the list below
[a-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Named Capture Group src_ip
(?<src_ip>[0-9.]+)
Match a single character present in the list below
[0-9.]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
Named Capture Group src_port
(?<src_port>[0-9]+)
Match a single character present in the list below
[0-9]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\) matches the character ) with index 4110 (2916 or 518) literally (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
->
matches the characters -> literally (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
Named Capture Group dest_iface
(?<dest_iface>[a-z]+)
Match a single character present in the list below
[a-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Named Capture Group dest_ip
(?<dest_ip>[0-9.]+)
Match a single character present in the list below
[0-9.]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
Named Capture Group dest_port
(?<dest_port>[0-9]+)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String