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

/
/
gxm

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""" ^=((?<component>[^ ]*(SUPERVISOR))|(?<severity>[^ ]*(INFO))).*\s+(?<time>[^ =]*)\s+[=]*\n(?<message>(?s)^(.*?)(?:(?:\r*\n){2})) """ test_str = ("=SUPERVISOR REPORT==== 5-Jul-2017::14:10:58 ===\n" " Supervisor: {<0.15737.0>,amqp_channel_sup_sup}\n" " Context: shutdown_errorhttps://regex101.com/r/QpRINz/1/tests\n" " Reason: shutdown\n" " Offender: [{nb_children,1},\n" " {name,channel_sup},\n" " {mfargs,\n" " {amqp_channel_sup,start_link,\n" " [direct,<0.15736.0>,\n" " <<\"<rabbit@rabbitmq-default-Control.3.15736.0>\">>]}},\n" " {restart_type,temporary},\n" " {shutdown,brutal_kill},\n" " {child_type,supervisor}]\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:03 ===\n" "Starting RabbitMQ 3.4.4 on Erlang 17.5.6\n" "Copyright (C) 2007-2014 GoPivotal, Inc.\n" "Licensed under the MPL. See http://www.rabbitmq.com/\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:03 ===\n" "node : rabbit@rabbitmq-default-Control\n" "home dir : /var/lib/rabbitmq\n" "config file(s) : /etc/rabbitmq/rabbitmq.config\n" "cookie hash : jlzhQcHOuBZ03iv7GFo/pQ==\n" "log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control.log\n" "sasl log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control-sasl.log\n" "database dir : /var/lib/rabbitmq/mnesia/rabbit@rabbitmq-default-Control\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "Limiting to approx 65436 file handles (58890 sockets)\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "Memory limit set to 58079MB of 145198MB total.\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "Disk free limit set to 50MB\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "msg_store_transient: using rabbit_msg_store_ets_index to provide index\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "msg_store_persistent: using rabbit_msg_store_ets_index to provide index\n\n" "=WARNING REPORT==== 24-Jul-2017::08:44:05 ===\n" "msg_store_persistent: rebuilding indices from scratch\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "started TCP Listener on 10.60.2.90:5672\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "accepting AMQP connection <0.4941.0> (10.60.2.82:47767 -> 10.60.2.90:5672)\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "accepting AMQP connection <0.4949.0> (10.60.2.82:47768 -> 10.60.2.90:5672)\n\n" "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" "accepting AMQP connection <0.4952.0> (10.60.2.82:47769 -> 10.60.2.90:5672)\n\n" "=SUPERVISOR REPORT==== 5-Jul-2017::23:11:58 ===\n" " Supervisor: {<0.23464.1>,amqp_channel_sup_sup}\n" " Context: shutdown_error\n" " Reason: shutdown\n" " Offender: [{nb_children,1},\n" " {name,channel_sup},\n" " {mfargs,\n" " {amqp_channel_sup,start_link,\n" " [direct,<0.23463.1>,\n" " <<\"<rabbit@rabbitmq-default-Control.3.23463.1>\">>]}},\n" " {restart_type,temporary},\n" " {shutdown,brutal_kill},\n" " {child_type,supervisor}]\n\n" "=SUPERVISOR REPORT==== 6-Jul-2017::06:20:58 ===\n" " Supervisor: {<0.22665.2>,amqp_channel_sup_sup}\n" " Context: shutdown_error\n" " Reason: shutdown\n" " Offender: [{nb_children,1},\n" " {name,channel_sup},\n" " {mfargs,\n" " {amqp_channel_sup,start_link,\n" " [direct,<0.22664.2>,\n" " <<\"<rabbit@rabbitmq-default-Control.3.22664.2>\">>]}},\n" " {restart_type,temporary},\n" " {shutdown,brutal_kill},\n" " {child_type,supervisor}]\n") matches = re.finditer(regex, test_str, re.VERBOSE | 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