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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"("log":".*?(?P<message>Company\s*[^\.]+.)\s*Company:\s*\[(?P<company>[0-9]+)\]\.\s*Rate:\s*\[(?P<rate>[0-9\.B\\\/s]+)\])"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #"{"kubernetes":{"pod_name":"throttler-0","namespace_name":"default","pod_id":"4f91ad3a-dd6f-4d56-b08a-2225edd67f9b","labels":{"CX_AZ":"us-east-2a","CX_CLOUDFLARE_SITE_ID":"ddb3ffb7b6beb645b97e4bab3fbcfc44","CX_CLUSTER_DNS":"usprod1.us-east-2.k8s-prod.coralogix.us","CX_DEPLOYABLE":"default","CX_DOMAIN":"coralogix.us","CX_ENV_CLASS":"usprod1","CX_ENV_ID":"usprod1","CX_ENV_TYPE":"prod","CX_ORG":"coralogix","CX_PRODUCT":"logs-data","CX_REGION":"us-east-2","CX_REPOSITORY":"throttler","CX_SERVICE_NAME":"throttler","CX_SERVICE_TYPE":"application","app_kubernetes_io_instance":"throttler","app_kubernetes_io_managed-by":"Helm","app_kubernetes_io_name":"throttler","controller-revision-hash":"throttler-8b99fb774","pipelines.coralogix.net\/managed-by":"eng-pipelines","pipelines.coralogix.net\/pipelines-version":"0.3.42","statefulset.kubernetes.io\/pod-name":"throttler-0"},"host":"ip-10-11-108-110.us-east-2.compute.internal","container_name":"throttler","docker_id":"90015d1ac334d32e38f69fa603b22b02a03182d00df7264a006f29b1f4fa066a","container_hash":"529726762838.dkr.ecr.eu-west-1.amazonaws.com\/throttler@sha256:1f8859d7e841f7f22d24bc882f6677199a747c0b40ee2f2ccb1cc4e10f46d4d3","container_image":"529726762838.dkr.ecr.eu-west-1.amazonaws.com\/throttler:392e6bdc"},"stream":"stdout","log":"[INFO] 2022-11-03T07:03:02,464 com.coralogix.throttler.model.Violation throttler-0af20f87-e6c8-4b51-8993-9e726245860a-StreamThread-1 Company transitioned into violated state. Company: [2010806]. Rate: [1298828.7833333334B\/s].","time":"2022-11-03T07:03:02.464514886Z"}"# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #""message":"$message","company":"$company","rate":"$rate",${1}"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) print(result)

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression