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

/
/
g

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"web\.\d{1,}\s+\|\s+(\{|>)" test_str = ("10:50:46 AM web.2 | > creating redis session\",\"time\":\"2016-05-18T17:50:46.161Z\",\"v\":0}\n" "10:50:46 AM web.3 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28296,\"level\":20,\"middleware\":\"cache-headers\",\"msg\":\"Loading middleware:: cache-headers\",\"time\":\"2016-05-18T17:50:46.172Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":40,\"msg\":\"LC-SESSION: set the secret for the session cookies in the config file, check lc-session config\",\"time\":\"2016-05-18T17:50:46.174Z\",\"v\":0}\n" "10:50:46 AM web.3 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28296,\"level\":20,\"middleware\":\"client-id\",\"msg\":\"Loading middleware:: client-id\",\"time\":\"2016-05-18T17:50:46.175Z\",\"v\":0}\n" "10:50:46 AM web.3 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28296,\"level\":20,\"middleware\":\"cookie-parser\",\"msg\":\"Loading middleware:: cookie-parser\",\"time\":\"2016-05-18T17:50:46.175Z\",\"v\":0}\n" "10:50:46 AM web.3 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28296,\"level\":20,\"middleware\":\"guid\",\"msg\":\"Loading middleware:: guid\",\"time\":\"2016-05-18T17:50:46.175Z\",\"v\":0}\n" "10:50:46 AM web.3 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28296,\"level\":20,\"middleware\":\"healthy\",\"msg\":\"Loading middleware:: healthy\",\"time\":\"2016-05-18T17:50:46.176Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":20,\"middleware\":\"sso\",\"msg\":\"Loading middleware:: sso\",\"time\":\"2016-05-18T17:50:46.177Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":30,\"msg\":\"SSO-MIDDLEWARE: Detecting SSO config\",\"time\":\"2016-05-18T17:50:46.177Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":30,\"msg\":\"SSO-MIDDLEWARE: enabling JANUS-SSO\",\"time\":\"2016-05-18T17:50:46.179Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":20,\"middleware\":\"timer\",\"msg\":\"Loading middleware:: timer\",\"time\":\"2016-05-18T17:50:46.180Z\",\"v\":0}\n" "10:50:46 AM web.1 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28278,\"level\":20,\"middleware\":\"cache-headers\",\"msg\":\"Loading middleware:: cache-headers\",\"time\":\"2016-05-18T17:50:46.180Z\",\"v\":0}\n" "10:50:46 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":20,\"middleware\":\"setTrackingData\",\"msg\":\"Loading middleware:: setTrackingData\",\"time\":\"2016-05-18T17:50:46.181Z\",\"v\":0}\n" "10:50:46 AM web.1 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28278,\"level\":20,\"middleware\":\"client-id\",\"msg\":\"Loading middleware:: client-id\",\"time\":\"2016-05-18T17:50:46.181Z\",\"v\":0}\n" "10:50:46 AM web.1 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28278,\"level\":20,\"middleware\":\"cookie-parser\",\"msg\":\"Loading middleware:: cookie-parser\",\"time\":\"2016-05-18T17:50:46.181Z\",\"v\":0}\n" "10:50:46 AM web.1 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28278,\"level\":20,\"middleware\":\"guid\",\"msg\":\"Loading middleware:: guid\",\"time\":\"2016-05-18T17:50:46.181Z\",\"v\":0}\n" "10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5001 is DOWN, reason: Layer4 connection problem, info: \"Connection refused\", check duration: 0ms. 2 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.\n" "10:50:42 AM web.1 | warn: --minUptime not set. Defaulting to: 1000ms\n" "10:50:42 AM web.1 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms\n" "10:50:42 AM web.2 | warn: --minUptime not set. Defaulting to: 1000ms\n" "10:50:42 AM web.2 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms\n" "10:50:42 AM web.3 | warn: --minUptime not set. Defaulting to: 1000ms\n" "10:50:42 AM web.3 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms\n" "10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5002 is DOWN, reason: Layer4 connection problem, info: \"Connection refused\", check duration: 0ms. 1 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.\n" "10:50:42 AM web.4 | warn: --minUptime not set. Defaulting to: 1000ms\n" "10:50:42 AM web.4 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms\n" "10:50:43 AM haproxy.1 | [WARNING] 138/105043 (28265) : Server nodes/node5003 is DOWN, reason: Layer4 connection problem, info: \"Connection refused\", check duration: 0ms. 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.\n" "10:50:43 AM haproxy.1 | [ALERT] 138/105043 (28265) : backend 'nodes' has no server available!\n" "10:50:43 AM web.2 | {\"name\":\"investor-webapp-registration\",\"hostname\":\"lasinvonboard101-prod.tlcinternal.com\",\"pid\":28283,\"level\":30,\"msg\":\"starting server on port 5001\",\"time\":\"2016-05-18T17:50:43.751Z\",\"v\":0}") matches = re.finditer(regex, test_str) 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