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

~
~
isg

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"<dl>(?:[^<]+|<(?!/?dl\b)|(?R))*+</dl>"# let regex = try! NSRegularExpression(pattern: pattern, options: [.caseInsensitive, .dotMatchesLineSeparators]) let testString = #""" <p> <span style="visibility:hidden" id="Synonyme"> <span id="Anker:Synonyme"></span> </span> </p> <div style="margin-bottom:-0.5em; font-weight:bold;" title="bedeutungsgleich gebrauchte Wörter">Synonyme:</div> <dl> <dd>[1] <a href="/w/index.php?title=Blutsverwandte&amp;action=edit&amp;redlink=1" class="new" title="Blutsverwandte (Seite nicht vorhanden)">Blutsverwandte</a>, <a href="/wiki/Sippe" title="Sippe">Sippe</a> <dl> <dd>[1a] <a href="/wiki/Kernfamilie" title="Kernfamilie">Kernfamilie</a></dd> <dd>[1b] <i>abwertend, salopp:</i> <a href="/wiki/Mischpoke" title="Mischpoke">Mischpoke</a></dd> </dl> </dd> <dd>[2] <a href="/wiki/Abart" title="Abart">Abart</a>, <a href="/wiki/Art" title="Art">Art</a>, <a href="/wiki/Bereich" title="Bereich">Bereich</a>, <a href="/wiki/Departement" title="Departement">Departement</a>, <a href="/wiki/Dialekt" title="Dialekt">Dialekt</a>, <a href="/wiki/Fach" title="Fach">Fach</a>, <a href="/wiki/Gattung" title="Gattung">Gattung</a>, <a href="/wiki/Genus" title="Genus">Genus</a>, <a href="/wiki/Geschlecht" title="Geschlecht">Geschlecht</a>, <a href="/wiki/Gruppe" title="Gruppe">Gruppe</a>, <a href="/wiki/Kategorie" title="Kategorie">Kategorie</a>, <a href="/wiki/Linie" title="Linie">Linie</a>, <a href="/wiki/Rasse" title="Rasse">Rasse</a>, <a href="/wiki/Reihe" title="Reihe">Reihe</a>, <a href="/wiki/Rubrik" title="Rubrik">Rubrik</a>, <a href="/wiki/Schlag" title="Schlag">Schlag</a> </dd> </dl> """# 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