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 = #"(PI~)([0-9]*)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" MSH|^~\&|EPIC|UMCG|||20180927143440||ADR^A19|18093|P|2.4||||||||||| MSA|CA|20180927023440|| QRD|20180927|R|I|20180927|||1^RD|1414141|DEM EVN|A19|20180927143440|||^^^^^^^^^^^^^|| PID|1||1414141^^^UMCG^PI~109819226||PROEFPERSOON&&PROEFPERSOON^J^X Y Z^^^^L^^^^NL1~PROEFPERSOON&&PROEFPERSOON^PIET^^^^^N^^^^NL1||19700101|M|PROEFPERSOON^PIET^^||PROEFLAAN 1C&PROEFLAAN&1C^^GRONINGEN^^9713GZ^NLD^L||050-1234567^P^PH^^^050^1234567~^NET^Internet^PIET@PROEFPERSOON.com~06-12345678^P^CP^^^06^12345678|06-87654321^P^PH^^^06^87654321|NEDERLANDS|||19764||||||Y||||||N|| ROL|1|UP|PP^Primary Care Provider|01001234^Huisarts^H^^^^^^Vektis^L|||||01^Huisartsen^Vektis||Straatweg 2&Straatweg&2^^Groningen^^9723AA^^O|050-3134102^WPN^PH~^NET^X.400^800013630 PV1|1|I|UG_V_A1VA^4^4-1^10^^^^^UMCG A1VA^^DEPID|NB||||||||||WOON|||||19764|CZ||||||||||||||||||||||||20180926143019||||||99996|||| AL1|1|SYSTEMISCH|^GEEN BEKENDE ALLERGIEEN^|||||| IN1|1||7119^^^UZOVI^PAYORID|CZ GROEP ZORGVERZEKERAAR UA (7119)|POSTBUS 4400&POSTBUS 4400&^^GOES^^4460CZ^||0113-274727^^^^^0113^274727|||||||||PROEFPERSOON^J^X Y Z.^^|Zelf|||Accepteren||1|||Ja||||||||||2552|ABC0123|||||||||||BEIDE|| IN2|||||Verzekeraar||||||||||||||||||||||||||||||||||||||||||||||||||||||||ABC0123||||||||| L|1|UP|PP^Primary Care Provider|01001234^Huisarts^H^^^^^^Vektis^L|||||01^Huisartsen^Vektis||Straatweg 2&Straatweg&2^^Groningen^^9723AA^^O|050-3134102^WPN^PH~^NET^X.400^800013630  """# 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