Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^Description\h*:\h*vusb0/iDRAC\h*Network/.*(?:.*\R)+?IPv4 Address\h+:\h*(\d{1,3}(?:\.\d{1,3}){3})", flags=re.MULTILINE) test_str = ("lo0\n" "Description : lo0\n" "Status : Up\n" "Interface Type : Loopback\n" "DHCP : Disabled\n" "MAC Address : 30-03-27-E3-3B-03\n" "FQDD : Not Applicable\n" "IPv4 Address : 127.0.0.1\n" "Subnet Mask : 255.0.0.0\n\n\n\n" "vmk0\n" "Description : vmnic0/Management Network/vmk0\n" "Status : Up\n" "Interface Type : Ethernet\n" "DHCP : Enabled\n" "DHCPServerV4 : 100.98.65.10\n" "MAC Address : 50-9A-4C-9C-99-8D\n" "FQDD : NIC.Embedded.1-1-1\n" "IPv4 Address : 100.98.68.239\n" "Subnet Mask : 255.255.252.0\n" "IPv6 Address : fe80::529a:4cff:fe9c:998d\n" "Prefix Length : 64\n" "IPv4 Gateway Address : 100.98.68.1\n" "IPv4 DNSServer Address 0: 10.7.7.7\n" "IPv4 DNSServer Address 1: 10.8.8.8\n\n\n\n" "vmk1\n" "Description : vusb0/iDRAC Network/vmk1\n" "Status : Up\n" "Interface Type : Ethernet\n" "DHCP : Disabled\n" "MAC Address : 00-50-56-6E-6F-99\n" "FQDD : Not Applicable\n" "IPv4 Address : 169.254.10.12\n" "Subnet Mask : 255.255.255.0\n" "IPv6 Address : fe80::250:56ff:fe6e:6f99\n" "Prefix Length : 64\n" "IPv4 DNSServer Address 0: 10.7.7.7\n" "IPv4 DNSServer Address 1: 10.8.8.8\n\n\n" "vmk2\n" "Description : vmnic1/iDRAC Network/vmk2\n" "Status : Up\n" "Interface Type : Ethernet\n" "DHCP : Disabled\n" "MAC Address : 00-50-56-6E-6F-99\n" "FQDD : Not Applicable\n" "IPv4 Address : 169.254.3.1\n" "Subnet Mask : 255.255.255.0\n" "IPv6 Address : fe80::250:56ff:fe6e:6f99\n" "Prefix Length : 64\n" "IPv4 DNSServer Address 0: 10.7.8.9\n" "IPv4 DNSServer Address 1: 10.3.2.1\n\n\n\n" "racadm>>") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html