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 = #"^(A(D|E|F|G|I|L|M|N|O|R|S|T|Q|U|W|X|Z)|B(A|B|D|E|F|G|H|I|J|L|M|N|O|R|S|T|V|W|Y|Z)|C(A|C|D|F|G|H|I|K|L|M|N|O|R|U|V|X|Y|Z)|D(E|J|K|M|O|Z)|E(C|E|G|H|R|S|T)|F(I|J|K|M|O|R)|G(A|B|D|E|F|G|H|I|L|M|N|P|Q|R|S|T|U|W|Y)|H(K|M|N|R|T|U)|I(D|E|Q|L|M|N|O|R|S|T)|J(E|M|O|P)|K(E|G|H|I|M|N|P|R|W|Y|Z)|L(A|B|C|I|K|R|S|T|U|V|Y)|M(A|C|D|E|F|G|H|K|L|M|N|O|Q|P|R|S|T|U|V|W|X|Y|Z)|N(A|C|E|F|G|I|L|O|P|R|U|Z)|OM|P(A|E|F|G|H|K|L|M|N|R|S|T|W|Y)|QA|R(E|O|S|U|W)|S(A|B|C|D|E|G|H|I|J|K|L|M|N|O|R|T|V|Y|Z)|T(C|D|F|G|H|J|K|L|M|N|O|R|T|V|W|Z)|U(A|G|M|S|Y|Z)|V(A|C|E|G|I|N|U)|W(F|S)|Y(E|T)|Z(A|M|W))$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""# 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