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
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(\d{4}-\d\d-\d\dT\d\d:\d\d:\d\d\.\d{3}Z)\s+(INFO|WARN|DEBUG|ERROR|FATAL|TRACE)\s+((?:\S+\s+){4})((?:\S+\]|\[\S+)?)(.*)" test_str = ("2019-11-14T04:25:00.123Z WARN http-nio-127.0.0.1-7440-exec-127 CorfuCompileProxy - accessInner: Encountered a trim exception while accessing version 120383907 on attempt 0\n" "2019-11-14T04:23:08.700Z INFO RpcManagerRequestCleanupTimer RpcManager - SYSTEM [nsx@6876 comp=\"nsx-manager\" level=\"INFO\" subcomp=\"manager\"] Rpc response not received for application FabricStats request com.vmware.nsx.management.agg.messaging.AggService$ClientDataRequestMsg from client 8ac94189-d611-4eb3-9b93-c3c3a8e3d36a with correlation id 287e690e-0a47-4459-a0bb-be36fe439068 in 432000000 msec.\n" "2019-11-14T04:24:04.072Z INFO MessagingObjectFactoryImpl-4-2 ExporterLastAckServiceImpl - - [nsx@6876 comp=\"nsx-manager\" level=\"INFO\" subcomp=\"manager\"] Found exporter with elaId = Node#a3844284-e626-11e9-a87b-005056bcc0c6#AggSvc-L2-Bridging, returning lastAck = 16507 \n" "2019-11-14T04:23:08.362Z INFO ActivityEventRecovery-1 ActivityCacheManager - - [nsx@6876 comp=\"nsx-manager\" level=\"INFO\" subcomp=\"manager\"] Handling activity 92d6a146-fa12-4889-a0ff-441087e047d0 completion event for 1 \n" "2019-11-14T04:23:08.362Z DEBUG ActivityEventRecovery-1 ActivityCacheManager - - [nsx@6876 comp=\"nsx-manager\" level=\"INFO\" subcomp=\"manager\"] Handling activity 92d6a146-fa12-4889-a0ff-441087e047d0 completion event for 1") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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