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""" ^=((?<component>[^ ]*(SUPERVISOR))|(?<severity>[^ ]*(INFO))).*\s+(?<time>[^ =]*)\s+[=]*\n(?<message>(?s)^(.*?)(?:(?:\r*\n){2})) """, flags=re.VERBOSE | re.MULTILINE) 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 = 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