Regular
Expressions
101
@regex101
Donate
Sponsor
Contact
Bug Reports & Feedback
Wiki
Whats new?
Regex Editor
Regex Library
Account
Regex Quiz
Settings
Live Help
Consider a donation
Become a sponsor
Save & Share
Save Regex
ctrl+s
Update Regex
ctrl+⇧+s
Flavor
PCRE2 (PHP >=7.3)
PCRE (PHP <7.3)
ECMAScript (JavaScript)
Python
Golang
Java 8
Function
Match
Substitution
List
Unit Tests
Tools
Code Generator
Regex Debugger
Sponsor
Jamstack at Scale
Explanation
/
(?sm)
interface
(
\S
*
)(?:
(?!
^
!
$
)
.
)*
port-security
.
*?
!
$
/
gm
(?sm)
match the remainder of the pattern with the following effective flags:
gms
s modifier:
s
ingle line. Dot matches newline characters
m modifier:
m
ulti line. Causes
^
and
$
to match the begin/end of each line (not only begin/end of string)
interface
matches the characters
interface
literally (case sensitive)
1st Capturing Group
(
\S
*
)
\S
matches any non-whitespace character (equivalent to
[^\r\n\t\f\v
]
)
*
matches the previous token between
zero
and
unlimited
times, as many times as possible, giving back as needed
(greedy)
Non-capturing group
(?:
(?!
^
!
$
)
.
)*
*
matches the previous token between
zero
and
unlimited
times, as many times as possible, giving back as needed
(greedy)
Negative Lookahead
(?!
^
!
$
)
Assert that the Regex below does not match
^
asserts position at start of a line
!
matches the character
!
with index
33
10
(
21
16
or
41
8
) literally (case sensitive)
$
asserts position at the end of a line
.
matches any character
port-security
matches the characters
port-security
literally (case sensitive)
.
matches any character
*?
matches the previous token between
zero
and
unlimited
times, as few times as possible, expanding as needed
(lazy)
!
matches the character
!
with index
33
10
(
21
16
or
41
8
) literally (case sensitive)
$
asserts position at the end of a line
Global pattern flags
g modifier:
g
lobal. All matches (don't return after first match)
m modifier:
m
ulti line. Causes
^
and
$
to match the begin/end of each line (not only begin/end of string)
Match Information
Your regular expression does not match the subject string.
Try launching the debugger to find out why.
Quick Reference
Regular Expression
v4
No Match
/
/
gm
Test String
Regular
Expressions
101
Please wait while the app is loading...
Please enable JavaScript to use this web application.