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

const regex = new RegExp('^(?P<LogTime>[A-Za-z0-9 :]+)\\s(?P<Hostname>[a-z0-9.-]+)\\s(?:ae_(?P<EnvIdentity>[a-z-]+):)\\s(?P<ModuleName>[a-zA-Z._]+)?\\s-\\s(?P<LogLevel>[A-Z]+)\\s-\\s(?:\\[JID:(gen:)?(?P<TaskId>[a-z0-9-]+)\\]\\s?)?(?:\\[FID:(?P<FieldId>[a-z0-9-]+)\\]\\s?)?(?:\\[Itin:(?P<Itinerary>[A-Za-z0-9]+)(?:->(?P<Step>[A-Z0-9a-z]+))?\\]\\s?)?(?:\\[State:(?P<State>[A-Za-z]+)\\]\\s?)?(?:alias=(?P<StepAlias>[a-z0-9]+),\\s)?(?:runtime_s=\\[?(?P<JobRuntimeSeconds>[0-9.]+)\\]?\\s?)?(?:metadata=(?P<Metadata>{.*}))?$', 'gm') const str = `Oct 30 09:54:06 production-ae-workers-d8c35 ae_env-name: ae.core.manager - INFO - [JID:gen:156364bc-fb25-11e9-8d15-02420af40b07] [FID:dead-f4rm-dead] [Itin:RunFieldForecastHourlyUpdate] [State:Finished] runtime_s=[16.03] metadata={"initiating_event": "hourly", "hourly_timestamp": "2019/10/30/14/00", "timestamp": "2019/10/30/08/00", "pd_meta": {"farm": {"uuid": "dead-beef-dead", "name": "My Farm Name"}, "field": {"uuid": "dead-b00b-dead", "name": "My house"}, "token": "REDACTED", "organization": {"uuid": "dead-f00d-dead", "name": "My Organization"}, "enterprise_group": {"uuid": "dead-gr0up-dead", "name": "My Group"}}, "field_uuid": "dead-f4rm-dead", "token": "REDACTED", "process_cfs": false, "seed_corn": false, "current_cropping": null, "daily_timestamp": "2019/10/30/08/00", "ye_target": "user", "priority": 3}`; // 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