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 = #"Match all movie titles containing a word end in 'tes'"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" Enemy at the Gates First Love, Last Rites Brüno 30 Minutes or Less The Ice Pirates The Mighty Macs Bridget Jones: The Edge of Reason Blood Diamond 50 First Dates The Greatest Game Ever Played The Pirates! Band of Misfits The World's Fastest Indian Van Wilder: Party Liaison 200 Cigarettes Midnight in Paris The Greatest Story Ever Told Kites The Pirates Who Don't Do Anything: A VeggieTales Movie Notes on a Scandal Pirates of the Caribbean: The Curse of the Black Pearl 88 Minutes The Ladykillers The Greatest Movie Ever Sold Pirates of the Caribbean: On Stranger Tides Bangkok Dangerous ATL 90 Minutes in Heaven The Greatest Show on Earth The Sweetest Thing Beastmaster 2: Through the Portal of Time From Dusk Till Dawn The White Countess Olympus Has Fallen Akira Bend It Like Beckham The Art of Getting By World's Greatest Dad The Greatest Irreplaceable Gridiron Gang 20 Dates Romance & Cigarettes Pirates of the Caribbean: At World's End Dick Tracy Bathory: Countess of Blood The Cure 15 Minutes The Past is a Grotesque Animal Pirates of the Caribbean: Dead Man's Chest Surrogates Sleep Tight """# 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