Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
gm

Test String

Code Generator

Generated Code

import Foundation let pattern = #"((?i)(Jair .*bolsonaro)|(bolsonaro)|(presidente .*bolsonaro)|(bilonaro)|(biroliro)|(biroslau)|(biroslini)|(biruleibes)|(bobonaro)|(bolno)|(bololaro)|(bolonaro)|(bolossauro)|(bolovo)|(bolro)|(bolso)|(bolsoanta)|(bolsobitch)|(bolsobostão)|(bolsolini)|(bolsonabo)|(bolzonóquio)|(bolzy)|(bonobo)|(boslo)|(bostonauro)|(bostossauro)|(bozolino)|(bozonabo)|(bubobauro)|(burronaro)|(capetão)|(chihuahua do Trump)|(coisa)|(coiso)|(frouxonaro)|(javier Bolsossauro)|(nalbossauro)|(salnorabo)|(silvonaro)|(soldado Bizonho)|(solnorabo)|(bolsonazi))"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" jair bolsonaro jair messisas bolsonaro bolsonaro presidente jair bolsonaro presidente jair messias bolsonaro JAIR bolsonaro Boldo Bilonaro Biroliro Biroslau Biroslini Biruleibes Bobonaro Bolno Bololaro Bolonaro Bolossauro Bolovo Bolro Bolso Bolsoanta Bolsobitch Bolsobostão Bolsolini Bolsonabo bolsonazi Bolzonóquio Bolzy Bonobo Boslo Bostonauro Bostossauro Bozolino Bozonabo Bubobauro Burronaro Capetão Chihuahua do Trump Coisa Coiso Frouxonaro Javier Bolsossauro Nalbossauro Salnorabo Silvonaro Soldado Bizonho Solnorabo """# 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