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

Code Generator

Language

Generated Code

import Foundation let pattern = #"^((?!V2).)*- Master\s*$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" AppMessages V2 - Dev AppMessages V2 - Master AWS - Octopus Release Bellhop Model V2 - Dev Bellhop Model V2 - Master BellHop Services V2 - Dev BellHop Services V2 - Master BellHop V2 - Dev BellHop V2 - Master BSG Log4j Extras V2 - Dev BSG Log4j Extras V2 - Master BSG-BOM - Dev BSG-BOM - Master BSG-BOM V2 - Dev BSG-BOM V2 - Master Core Model V2 - Dev Core Model V2 - Master Core Services V2 - Dev Core Services V2 - Master DealerLocator - Dev EMS Services V2 - Dev EMS Services V2 - Master Entitlements REST API V2 - Dev Entitlements REST API V2 - Master Entitlements Services V2 - Dev Entitlements Services V2 - Master Entitlements SOAP API V2 - Dev Entitlements SOAP API V2 - Master FlexNet Services - Dev FlexNet Services - Master GetNodeInfo BusSys-Build-Slave-01 GetNodeInfo BusSys_Corp_Build_Slave GetNodeInfo Master Laipac Services V2 - Dev Laipac Services V2 - Master LDK Services V2 - Dev LDK Services V2 - Master LicenseAdmin - Dev LicenseAdmin - Master List All Jobs Lite Services V2 - Dev Lite Services V2 - Master LiteFlexNetIntegration V2 - Dev LiteFlexNetIntegration V2 - Master LiteIntegration - Dev LiteIntegration - Master Messaging Services V2 - Dev Messaging Services V2 - Master MTPConsumer - Dev MTPConsumer - Master OptionKeys - Dev OptionKeys - Master OptionKeysAPI - Dev OptionKeysAPI - Master Panther REST API V2 - Dev Pools API V2 - Dev Pools API V2 - Master Pools Model V2 - Dev Pools Model V2 - Master Pools Services V2 - Dev Pools Services V2 - Master Preconfigured API V2 - Dev Preconfigured API V2 - Master SCL Client V2 - Dev SCL Client V2 - Master SentinelCloud Services V2 - Dev SentinelCloud Services V2 - Master SubscriptionManager V2 - Dev SubscriptionManager V2 - Master TermsOfService - Master Test Support V2 - Dev Test Support V2 - Master Tid Services V2 - Dev Tid Services V2 - Master Upload templates to S3 - branch2Dev Upload templates to S3 - Dev Upload templates to S3 - Master Upload templates to S3 - Test VirtualWarehouse - Dev VirtualWarehouse - Master VirtualWarehouse Services V2 - Dev VirtualWarehouse Services V2 - Master VW Lite API - Dev VW Lite API - Master VW Remedy Events - Dev VW Remedy Events - Master VW Remedy Events Consumer - Dev VW Remedy Events Consumer - Master VW Remedy Events Lib - Dev VW Remedy Events Lib - Master VW Scheduled Tasks V2 - Dev VW Scheduled Tasks V2 - Master VW Sentinel V2 - Dev VW Sentinel V2 - Master VW Subscriptions V2 - Dev VW Subscriptions V2 - Master VW5 - Dev VW5 - Master WooCommerce API V2 - Dev WooCommerce API V2 - Master WooCommerce Model V2 - Dev WooCommerce Model V2 - Master WooCommerce Services V2 - Dev WooCommerce Services V2 - Master """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } 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