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

/
/
gmx

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"^(?:([0-1])|(2)|(3))(?(1)[0-9])(?(2)(?:([0-8])|(9)))(?(3)[0-1])\/(?:(01|03|05|07|09|11)|(04|06|08|10|12)|(02))(?(3)(?(8)(?!)))\/(?:(04|08|12|16|20|24|28|32|36|40|44|48|52|56|60|64|68|72|76|80|84|88|92|96)|(\d\d))(?:(00)|(04|08|12|16|20|24|28|32|36|40|44|48|52|56|60|64|68|72|76|80|84|88|92|96)|\d{2})(?(2)(?(5)(?(8)(?(11)(?(9)|(?!))|(?(12)|(?!))))))"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace]) let testString = #""" 29/02/1200 29/02/1400 01/01/1999 02/01/1999 03/01/1999 04/01/1999 05/01/1999 06/01/1999 07/01/1999 08/01/1999 09/01/1999 10/01/1999 11/01/1999 12/01/1999 13/01/1999 14/01/1999 15/01/1999 16/01/1999 17/01/1999 18/01/1999 19/01/1999 20/01/1999 21/01/1999 22/01/1999 23/01/1999 24/01/1999 25/01/1999 26/01/1999 27/01/1999 28/01/1999 29/01/1999 30/01/1999 31/01/1999 01/02/1999 02/02/1999 03/02/1999 04/02/1999 05/02/1999 06/02/1999 07/02/1999 08/02/1999 09/02/1999 10/02/1999 11/02/1999 12/02/1999 13/02/1999 14/02/1999 15/02/1999 16/02/1999 17/02/1999 18/02/1999 19/02/1999 20/02/1999 21/02/1999 22/02/1999 23/02/1999 24/02/1999 25/02/1999 26/02/1999 27/02/1999 28/02/1999 01/03/1999 02/03/1999 03/03/1999 04/03/1999 05/03/1999 06/03/1999 07/03/1999 08/03/1999 09/03/1999 10/03/1999 11/03/1999 12/03/1999 13/03/1999 14/03/1999 15/03/1999 16/03/1999 17/03/1999 18/03/1999 19/03/1999 20/03/1999 21/03/1999 22/03/1999 23/03/1999 24/03/1999 25/03/1999 26/03/1999 27/03/1999 28/03/1999 29/03/1999 30/03/1999 31/03/1999 01/04/1999 02/04/1999 03/04/1999 04/04/1999 05/04/1999 06/04/1999 07/04/1999 08/04/1999 09/04/1999 10/04/1999 11/04/1999 12/04/1999 13/04/1999 14/04/1999 15/04/1999 16/04/1999 17/04/1999 18/04/1999 19/04/1999 20/04/1999 21/04/1999 22/04/1999 23/04/1999 24/04/1999 25/04/1999 26/04/1999 27/04/1999 28/04/1999 29/04/1999 30/04/1999 01/05/1999 02/05/1999 03/05/1999 04/05/1999 05/05/1999 06/05/1999 07/05/1999 08/05/1999 09/05/1999 10/05/1999 11/05/1999 12/05/1999 13/05/1999 14/05/1999 15/05/1999 16/05/1999 17/05/1999 18/05/1999 19/05/1999 20/05/1999 21/05/1999 22/05/1999 23/05/1999 24/05/1999 25/05/1999 26/05/1999 27/05/1999 28/05/1999 29/05/1999 30/05/1999 31/05/1999 01/06/1999 02/06/1999 03/06/1999 04/06/1999 05/06/1999 06/06/1999 07/06/1999 08/06/1999 09/06/1999 10/06/1999 11/06/1999 12/06/1999 13/06/1999 14/06/1999 15/06/1999 16/06/1999 17/06/1999 18/06/1999 19/06/1999 20/06/1999 21/06/1999 22/06/1999 23/06/1999 24/06/1999 25/06/1999 26/06/1999 27/06/1999 28/06/1999 29/06/1999 30/06/1999 01/07/1999 02/07/1999 03/07/1999 04/07/1999 05/07/1999 06/07/1999 07/07/1999 08/07/1999 09/07/1999 10/07/1999 11/07/1999 12/07/1999 13/07/1999 14/07/1999 15/07/1999 16/07/1999 17/07/1999 18/07/1999 19/07/1999 20/07/1999 21/07/1999 22/07/1999 23/07/1999 24/07/1999 25/07/1999 26/07/1999 27/07/1999 28/07/1999 29/07/1999 30/07/1999 31/07/1999 01/08/1999 02/08/1999 03/08/1999 04/08/1999 05/08/1999 06/08/1999 07/08/1999 08/08/1999 09/08/1999 10/08/1999 11/08/1999 12/08/1999 13/08/1999 14/08/1999 15/08/1999 16/08/1999 17/08/1999 18/08/1999 19/08/1999 20/08/1999 21/08/1999 22/08/1999 23/08/1999 24/08/1999 25/08/1999 26/08/1999 27/08/1999 28/08/1999 29/08/1999 30/08/1999 31/08/1999 01/09/1999 02/09/1999 03/09/1999 04/09/1999 05/09/1999 06/09/1999 07/09/1999 08/09/1999 09/09/1999 10/09/1999 11/09/1999 12/09/1999 13/09/1999 14/09/1999 15/09/1999 16/09/1999 17/09/1999 18/09/1999 19/09/1999 20/09/1999 21/09/1999 22/09/1999 23/09/1999 24/09/1999 25/09/1999 26/09/1999 27/09/1999 28/09/1999 29/09/1999 30/09/1999 01/10/1999 02/10/1999 03/10/1999 04/10/1999 05/10/1999 06/10/1999 07/10/1999 08/10/1999 09/10/1999 10/10/1999 11/10/1999 12/10/1999 13/10/1999 14/10/1999 15/10/1999 16/10/1999 17/10/1999 18/10/1999 19/10/1999 20/10/1999 21/10/1999 22/10/1999 23/10/1999 24/10/1999 25/10/1999 26/10/1999 27/10/1999 28/10/1999 29/10/1999 30/10/1999 31/10/1999 01/11/1999 02/11/1999 03/11/1999 04/11/1999 05/11/1999 06/11/1999 07/11/1999 08/11/1999 09/11/1999 10/11/1999 11/11/1999 12/11/1999 13/11/1999 14/11/1999 15/11/1999 16/11/1999 17/11/1999 18/11/1999 19/11/1999 20/11/1999 21/11/1999 22/11/1999 23/11/1999 24/11/1999 25/11/1999 26/11/1999 27/11/1999 28/11/1999 29/11/1999 30/11/1999 01/12/1999 02/12/1999 03/12/1999 04/12/1999 05/12/1999 06/12/1999 07/12/1999 08/12/1999 09/12/1999 10/12/1999 11/12/1999 12/12/1999 13/12/1999 14/12/1999 15/12/1999 16/12/1999 17/12/1999 18/12/1999 19/12/1999 20/12/1999 21/12/1999 22/12/1999 23/12/1999 24/12/1999 25/12/1999 26/12/1999 27/12/1999 28/12/1999 29/12/1999 30/12/1999 31/12/1999 01/01/2000 02/01/2000 03/01/2000 04/01/2000 05/01/2000 06/01/2000 07/01/2000 08/01/2000 09/01/2000 10/01/2000 11/01/2000 12/01/2000 13/01/2000 14/01/2000 15/01/2000 16/01/2000 17/01/2000 18/01/2000 19/01/2000 20/01/2000 21/01/2000 22/01/2000 23/01/2000 24/01/2000 25/01/2000 26/01/2000 27/01/2000 28/01/2000 29/01/2000 30/01/2000 31/01/2000 01/02/2000 02/02/2000 03/02/2000 04/02/2000 05/02/2000 06/02/2000 07/02/2000 08/02/2000 09/02/2000 10/02/2000 11/02/2000 12/02/2000 13/02/2000 14/02/2000 15/02/2000 16/02/2000 17/02/2000 18/02/2000 19/02/2000 20/02/2000 21/02/2000 22/02/2000 23/02/2000 24/02/2000 25/02/2000 26/02/2000 27/02/2000 28/02/2000 29/02/2000 01/03/2000 02/03/2000 03/03/2000 04/03/2000 05/03/2000 06/03/2000 07/03/2000 08/03/2000 09/03/2000 10/03/2000 11/03/2000 12/03/2000 13/03/2000 14/03/2000 15/03/2000 16/03/2000 17/03/2000 18/03/2000 19/03/2000 20/03/2000 21/03/2000 22/03/2000 23/03/2000 24/03/2000 25/03/2000 26/03/2000 27/03/2000 28/03/2000 29/03/2000 30/03/2000 31/03/2000 01/04/2000 02/04/2000 03/04/2000 04/04/2000 05/04/2000 06/04/2000 07/04/2000 08/04/2000 09/04/2000 10/04/2000 11/04/2000 12/04/2000 13/04/2000 14/04/2000 15/04/2000 16/04/2000 17/04/2000 18/04/2000 19/04/2000 20/04/2000 21/04/2000 22/04/2000 23/04/2000 24/04/2000 25/04/2000 26/04/2000 27/04/2000 28/04/2000 29/04/2000 30/04/2000 01/05/2000 02/05/2000 03/05/2000 04/05/2000 05/05/2000 06/05/2000 07/05/2000 08/05/2000 09/05/2000 10/05/2000 11/05/2000 12/05/2000 13/05/2000 14/05/2000 15/05/2000 16/05/2000 17/05/2000 18/05/2000 19/05/2000 20/05/2000 21/05/2000 22/05/2000 23/05/2000 24/05/2000 25/05/2000 26/05/2000 27/05/2000 28/05/2000 29/05/2000 30/05/2000 31/05/2000 01/06/2000 02/06/2000 03/06/2000 04/06/2000 05/06/2000 06/06/2000 07/06/2000 08/06/2000 09/06/2000 10/06/2000 11/06/2000 12/06/2000 13/06/2000 14/06/2000 15/06/2000 16/06/2000 17/06/2000 18/06/2000 19/06/2000 20/06/2000 21/06/2000 22/06/2000 23/06/2000 24/06/2000 25/06/2000 26/06/2000 27/06/2000 28/06/2000 29/06/2000 30/06/2000 01/07/2000 02/07/2000 03/07/2000 04/07/2000 05/07/2000 06/07/2000 07/07/2000 08/07/2000 09/07/2000 10/07/2000 11/07/2000 12/07/2000 13/07/2000 14/07/2000 15/07/2000 16/07/2000 17/07/2000 18/07/2000 19/07/2000 20/07/2000 21/07/2000 22/07/2000 23/07/2000 24/07/2000 25/07/2000 26/07/2000 27/07/2000 28/07/2000 29/07/2000 30/07/2000 31/07/2000 01/08/2000 02/08/2000 03/08/2000 04/08/2000 05/08/2000 06/08/2000 07/08/2000 08/08/2000 09/08/2000 10/08/2000 11/08/2000 12/08/2000 13/08/2000 14/08/2000 15/08/2000 16/08/2000 17/08/2000 18/08/2000 19/08/2000 20/08/2000 21/08/2000 22/08/2000 23/08/2000 24/08/2000 25/08/2000 26/08/2000 27/08/2000 28/08/2000 29/08/2000 30/08/2000 31/08/2000 01/09/2000 02/09/2000 03/09/2000 04/09/2000 05/09/2000 06/09/2000 07/09/2000 08/09/2000 09/09/2000 10/09/2000 11/09/2000 12/09/2000 13/09/2000 14/09/2000 15/09/2000 16/09/2000 17/09/2000 18/09/2000 19/09/2000 20/09/2000 21/09/2000 22/09/2000 23/09/2000 24/09/2000 25/09/2000 26/09/2000 27/09/2000 28/09/2000 29/09/2000 30/09/2000 01/10/2000 02/10/2000 03/10/2000 04/10/2000 05/10/2000 06/10/2000 07/10/2000 08/10/2000 09/10/2000 10/10/2000 11/10/2000 12/10/2000 13/10/2000 14/10/2000 15/10/2000 16/10/2000 17/10/2000 18/10/2000 19/10/2000 20/10/2000 21/10/2000 22/10/2000 23/10/2000 24/10/2000 25/10/2000 26/10/2000 27/10/2000 28/10/2000 29/10/2000 30/10/2000 31/10/2000 01/11/2000 02/11/2000 03/11/2000 04/11/2000 05/11/2000 06/11/2000 07/11/2000 08/11/2000 09/11/2000 10/11/2000 11/11/2000 12/11/2000 13/11/2000 14/11/2000 15/11/2000 16/11/2000 17/11/2000 18/11/2000 19/11/2000 20/11/2000 21/11/2000 22/11/2000 23/11/2000 24/11/2000 25/11/2000 26/11/2000 27/11/2000 28/11/2000 29/11/2000 30/11/2000 01/12/2000 02/12/2000 03/12/2000 04/12/2000 05/12/2000 06/12/2000 07/12/2000 08/12/2000 09/12/2000 10/12/2000 11/12/2000 12/12/2000 13/12/2000 14/12/2000 15/12/2000 16/12/2000 17/12/2000 18/12/2000 19/12/2000 20/12/2000 21/12/2000 22/12/2000 23/12/2000 24/12/2000 25/12/2000 26/12/2000 27/12/2000 28/12/2000 29/12/2000 30/12/2000 31/12/2000 """# 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