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

Generated Code

import Foundation let pattern = #"Json(?<json_output>[\s\S\d\D\w\W]*)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" ```json [ { "Place": { "Name": "Les Catacombes de Paris", "Google_place_id": "ChIJVXealLU_xkcRja_At0z9AGY", "City": "Paris", "Region": "Île-de-France", "Country": "France", "Cultural_type": "Historical", "Facts": { "Historical_facts": { "FACT_TYPE": "Did you know ?", "FACTS": [ "Les Catacombes de Paris ont été créées à la fin du 18ème siècle pour résoudre le problème de surpeuplement des cimetières de la ville." ], "INTERACTION": [ "Savez-vous pourquoi les catacombes ont été construites ?" ], "CATEGORY": "Historical_facts" }, "Architectural_facts": { "FACT_TYPE": "Fun fact", "FACTS": [ "Les catacombes sont faites d’anciens tunnels de carrières transformés pour stocker les ossements de plus de six millions de Parisiens." ], "INTERACTION": [ "Combien de personnes pensez-vous que les catacombes peuvent contenir ?" ], "CATEGORY": "Architectural_facts" }, "Scientific_facts": { "FACT_TYPE": "Wow", "FACTS": [ "Les conditions dans les catacombes, qui sont fraîches et humides, permettent une bonne conservation des ossements." ], "INTERACTION": [ "Que pensez-vous que l'humidité fait aux ossements ?" ], "CATEGORY": "Scientific_facts" }, "Mystery_legends_facts": { "FACT_TYPE": "Did you know ?", "FACTS": [ "Une légende urbaine raconte qu’il y a un cinéma secret dans les catacombes !", "Il paraîtrait que des groupes se réunissent ici pour regarder des films." ], "INTERACTION": [ "Aimeriez-vous visiter un cinéma caché ?", "Quel genre de film pensez-vous qu’ils projettent là-bas ?" ], "CATEGORY": "Mystery_legends_facts" } } } } ] ``` """# 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