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

/
/
sU

Test String

Code Generator

Language

Generated Code

import Foundation // WARNING: You included a flag that Swift doesn't support: U // When this flag is set, it inverts the "greediness" of the quantifiers so that they are not greedy by default, but become greedy if followed by '?'. // As an alternative, this effect can also be achieved by setting a (?U) modifier setting within the pattern or by a question mark behind a quantifier (e.g. .*?). let pattern = #"\d+?[\r\n]+(.*)3.2.P.4.4.\s+Justification\s+of\s+Specifications"# let regex = try! NSRegularExpression(pattern: pattern, options: .dotMatchesLineSeparators) let testString = #""" 26 Data related to the point SP-WFI-21-Room process fluids Sampling Date:16/04/2007 28 Data related to pint SP-WFI-21-Room process fluids Sampling Date: 20/04/2007 TEST SPECIFICATIONS RESULTS T.O.C. ≤ 500 ppb 6ppb Conductivity at 25°C ≤ 1.3 μS.cm-1 1.1 μS.cm-1 Data related to the point of use UP-WFI-07 Sampling Date: 20/04/2007 TEST SPECIFICATIONS RESULTS Appearance Clear and colourless liquid Conforms pH 5.0 – 7.0 6.20 Oxidable substances Conforms Conforms Conductivity at 25°C ≤ 1.3 μS.cm-1 1.1 μS.cm-1 0 microrg./100ml Reference guidelines − 3AQ11A: Specifications and Control Tests on the Finished Product - EUDRALEX Volume 3A − Topic Q6A, Step 4 Note for Guidance Specifications: Test procedures and Acceptance Criteria for New Drug Substances and New Drug Products: Chemical Substances (CPMP/ICH/367/96 - Adopted Nov. 99) 29 3.2.P.4.2 Analytical Procedures All the analytical procedures related to the control of excipients are those described in the corresponding Ph. Eur. monographs current edition (refer to 3.2.P.4.1). Reference guidelines − Topic Q2A, Step 5 Note for Guidance on Validation of Analytical Methods: Definitions and Terminology (CPMP/ICH/381/95 - adopted Nov. 94) − 3AQ14A: Validation of Analytical Procedures: Definition and Terminology - EUDRALEX Volume 3A − 3AQ13A: Validation of Analytical Procedures: Methodology - EUDRALEX Volume 3A − Topic Q6A, Step 4 Note for Guidance Specifications: Test procedures and Acceptance Criteria for New Drug Substances and New Drug Products: Chemical Substances (CPMP/ICH/367/96 - Adopted Nov. 99) 3.2.P.4.3 Validation of Analytical Procedures All the analytical procedures proposed to control the excipients are those reported in Ph. Eur. monographs current edition and no variation has been introduced; each method is validated concerning specificity and linearity, in order to grant suitability of the instruments used. Reference guidelines: − Topic Q2A, Step 5 Note for Guidance on Validation of Analytical Methods: Definitions and Terminology (CPMP/ICH/381/95 - adopted Nov. 94) − 3AQ14A: Validation of Analytical Procedures: Definition and Terminology - EUDRALEX Volume 3A − 3AQ13A: Validation of Analytical Procedures: Methodology - EUDRALEX Volume 3A 3.2.P.4.4. Justification of Specifications """# let stringRange = NSRange(location: 0, length: testString.utf16.count) if let firstMatch = regex.firstMatch(in: testString, range: stringRange) { let result: [String] = (1 ..< firstMatch.numberOfRanges).map { (testString as NSString).substring(with: firstMatch.range(at: $0)) } print(result) } else { print("No matches were found.") }

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