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

const regex = /^=((?<component>[^ ]*(SUPERVISOR))|(?<severity>[^ ]*(INFO))).*\s+(?<time>[^ =]*)\s+[=]*\n(?<message>(?s)^(.*?)(?:(?:\r*\n){2}))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^=((?<component>[^ ]*(SUPERVISOR))|(?<severity>[^ ]*(INFO))).*\\s+(?<time>[^ =]*)\\s+[=]*\\n(?<message>(?s)^(.*?)(?:(?:\\r*\\n){2}))', 'gm') const str = `=SUPERVISOR REPORT==== 5-Jul-2017::14:10:58 === Supervisor: {<0.15737.0>,amqp_channel_sup_sup} Context: shutdown_errorhttps://regex101.com/r/QpRINz/1/tests Reason: shutdown Offender: [{nb_children,1}, {name,channel_sup}, {mfargs, {amqp_channel_sup,start_link, [direct,<0.15736.0>, <<"<rabbit@rabbitmq-default-Control.3.15736.0>">>]}}, {restart_type,temporary}, {shutdown,brutal_kill}, {child_type,supervisor}] =INFO REPORT==== 24-Jul-2017::08:44:03 === Starting RabbitMQ 3.4.4 on Erlang 17.5.6 Copyright (C) 2007-2014 GoPivotal, Inc. Licensed under the MPL. See http://www.rabbitmq.com/ =INFO REPORT==== 24-Jul-2017::08:44:03 === node : rabbit@rabbitmq-default-Control home dir : /var/lib/rabbitmq config file(s) : /etc/rabbitmq/rabbitmq.config cookie hash : jlzhQcHOuBZ03iv7GFo/pQ== log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control.log sasl log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control-sasl.log database dir : /var/lib/rabbitmq/mnesia/rabbit@rabbitmq-default-Control =INFO REPORT==== 24-Jul-2017::08:44:05 === Limiting to approx 65436 file handles (58890 sockets) =INFO REPORT==== 24-Jul-2017::08:44:05 === Memory limit set to 58079MB of 145198MB total. =INFO REPORT==== 24-Jul-2017::08:44:05 === Disk free limit set to 50MB =INFO REPORT==== 24-Jul-2017::08:44:05 === msg_store_transient: using rabbit_msg_store_ets_index to provide index =INFO REPORT==== 24-Jul-2017::08:44:05 === msg_store_persistent: using rabbit_msg_store_ets_index to provide index =WARNING REPORT==== 24-Jul-2017::08:44:05 === msg_store_persistent: rebuilding indices from scratch =INFO REPORT==== 24-Jul-2017::08:44:05 === started TCP Listener on 10.60.2.90:5672 =INFO REPORT==== 24-Jul-2017::08:44:05 === accepting AMQP connection <0.4941.0> (10.60.2.82:47767 -> 10.60.2.90:5672) =INFO REPORT==== 24-Jul-2017::08:44:05 === accepting AMQP connection <0.4949.0> (10.60.2.82:47768 -> 10.60.2.90:5672) =INFO REPORT==== 24-Jul-2017::08:44:05 === accepting AMQP connection <0.4952.0> (10.60.2.82:47769 -> 10.60.2.90:5672) =SUPERVISOR REPORT==== 5-Jul-2017::23:11:58 === Supervisor: {<0.23464.1>,amqp_channel_sup_sup} Context: shutdown_error Reason: shutdown Offender: [{nb_children,1}, {name,channel_sup}, {mfargs, {amqp_channel_sup,start_link, [direct,<0.23463.1>, <<"<rabbit@rabbitmq-default-Control.3.23463.1>">>]}}, {restart_type,temporary}, {shutdown,brutal_kill}, {child_type,supervisor}] =SUPERVISOR REPORT==== 6-Jul-2017::06:20:58 === Supervisor: {<0.22665.2>,amqp_channel_sup_sup} Context: shutdown_error Reason: shutdown Offender: [{nb_children,1}, {name,channel_sup}, {mfargs, {amqp_channel_sup,start_link, [direct,<0.22664.2>, <<"<rabbit@rabbitmq-default-Control.3.22664.2>">>]}}, {restart_type,temporary}, {shutdown,brutal_kill}, {child_type,supervisor}] `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions