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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = #"(?:(Dim|Public|Private) )(?:(WithEvents) )?(?:(?:(?!Declare)(?!Type)(?!Enum)(?!Const)(\w*))(\(\))?)(?: As )?(?:(New) )?(\w*)(, [\w ,\(\)]*)?"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" Attribute VB_Name = "mdl_WbkInits" Option Compare Database Public WithEvents ue_u23 As New String, soumeth_34ing as somethnig, asi As Anthere item, Maybe lastOne Public ueu As Variant Dim ueu Public Declare Function IIDFromString Lib "ole32" (ByVal lpsz As Long, ByRef lpiid As UUID) As Long Private Declare Function IIDFromString Lib "ole32" (ByVal lpsz As Long, ByRef lpiid As UUID) As Long Private Declare PtrSafe Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hwnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long Private Type UUID 'GUID Data1 As Long Data2 As Integer Data3 As Integer Data4(7) As Byte End Type Public Enum e_ControlEventCatch e_onClick e_onChange e_onUpdate e_onUpdated e_onDblClick e_onFocus e_onExtClick e_onExtDblClick e_onActivate e_onDeActivate End Enum Public Const IID_IDispatch As String = "{00020400-0000-0000-C000-000000000046}" Const OBJID_NATIVEOM As Long = &HFFFFFFF0 """# 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