Regular Expressions 101

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  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
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  • Substitution
  • A single character of: a, b or c
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression


Test String

Code Generator

Generated Code

import Foundation let pattern = #"\\"\d{1,3}cm\\""# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" "<?xml version=\"1.0\" standalone=\"no\"?>", "<svg xmlns=\"\" version=\"1.1\" width=\"1250cm\" height=\"1250cm\">", "<desc>9W43OV00W8JKMA1IJNEYAM1WTG9AZH8K10LC</desc>", "<g id=\"HMLW03D1BYIQ\" fill=\"red\">", "<rect x=\"252cm\" y=\"252cm\" width=\"252cm\" height=\"252cm\"/>", "<rect x=\"72cm\" y=\"72cm\" width=\"72cm\" height=\"72cm\"/>", "<rect x=\"131cm\" y=\"131cm\" width=\"131cm\" height=\"131cm\"/>", "<rect x=\"228cm\" y=\"228cm\" width=\"228cm\" height=\"228cm\"/>", "<rect x=\"240cm\" y=\"240cm\" width=\"240cm\" height=\"240cm\"/>", "<rect x=\"232cm\" y=\"232cm\" width=\"232cm\" height=\"232cm\"/>", "<rect x=\"192cm\" y=\"192cm\" width=\"192cm\" height=\"192cm\"/>", "<rect x=\"0cm\" y=\"0cm\" width=\"0cm\" height=\"0cm\"/>", "<rect x=\"0cm\" y=\"0cm\" width=\"0cm\" height=\"0cm\"/>", "<rect x=\"0cm\" y=\"0cm\" width=\"0cm\" height=\"0cm\"/>", "<rect x=\"65cm\" y=\"65cm\" width=\"65cm\" height=\"65cm\"/>", "<rect x=\"81cm\" y=\"81cm\" width=\"81cm\" height=\"81cm\"/>", "<rect x=\"65cm\" y=\"65cm\" width=\"65cm\" height=\"65cm\"/>", "<rect x=\"80cm\" y=\"80cm\" width=\"80cm\" height=\"80cm\"/>", "<rect x=\"82cm\" y=\"82cm\" width=\"82cm\" height=\"82cm\"/>", "<rect x=\"81cm\" y=\"81cm\" width=\"81cm\" height=\"81cm\"/>", "</g>" """# 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: