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

/
/
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"^(((([A-Z]+-)?((\d{2})([A-Z]{3})(\d{2}))?([A-Z]{3})?( )?((.[0-9A-Z]{3})|([0-9A-Z]{2}))( )([X][\/])?((E\/)|(B\/)|(T\/)|(L\/))*(([A-Z][\/-])?[A-Z]{3})?(?!\d{1,3}[A-Z\s])( )?(((E\/XXX)?|([Q]{1}(( )?([A-Z]{3})([A-Z]{3}))?(\d+M)?(\d{1,6}(\.\d{1,4})?))?|(M( )?([A-Z]{6})?( )?(\d{1,6}(\.\d{1,4})?)?)?|([R]{1}(\d+M)?(\d{1,6}(\.\d{1,4})?))?|(([0-9])*S(\d+M)?(\d{1,6}(\.\d{1,4})?))?|(M?\/(IT))|(M?\/(BT))|(\/\/([A-Z]{3})))( )?)*(\d+M( )?)?((?![0-9][A-Z])\d{1,6}(\.\d{1,4})?( )?)?((?<=[0-9])((?![A-Z][A-Z0-9]( )([A-Z]\/)?[A-Z]{3}|NUC|END|[A-Z]{3}( )[0-9])|(?=[A-Z][A-Z0-9]( )NUC))[A-Z][A-Z0-9\/]{0,8})?(( )?(([Q]{1}(\d+M)?(\d{1,6}(\.\d{1,4})?))|(P R\/([A-Z]{3})(\/)?([A-Z]{3})?( )?(\d+M)?(\d{1,6}(\.\d{1,4})?))|(P( )([A-Z]{6})( )?([A-Z]{6})?( )?(\d+M)?(\d{1,6}(\.\d{1,4})?))|(M( )?([A-Z]{6})?( )?(\d{1,6}(\.\d{1,4})?)?)|(H( )([A-Z]{6})( )?(\d{1,6}(\.\d{1,4})?))|(U( )(( )?([A-Z]{6}))+( )?(\d{1,6}(\.\d{1,4})?))|(C\/([A-Z]{3})(( )?[A-Z]{6})*( )?(\d{1,6}(\.\d{1,4})?))|(D( )((([A-Z])+\/)?([A-Z]{6})( )?((M)|(\d+M)|( )|(\d{1,6}(\.\d{1,4})?))( )?)+)|(\/-([A-Z]{3}))|(\/\/([A-Z]{3})))?( )?)*)+)+)( )?((( )?([A-Z]{3})( )?(\d{1,6}(\.\d{1,4})?))( )?(END)|(END))( )?(ROE( )?\d+(\.\d+)?)?(.*)?$"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #"SIN UB X/RGN101.29ESGR UB NYT110.00YOW UB RGN110.00YOW RGN UB SIN 101"# 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