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

/
/
is

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?:cmdlet|get-alias)|(?:help.+?(?:cmdlet|get-alias))"# let regex = try! NSRegularExpression(pattern: pattern, options: [.caseInsensitive, .dotMatchesLineSeparators]) let testString = #""" PS M:\> get-help TOPIC Get-Help SHORT DESCRIPTION Displays help about Windows PowerShell cmdlets and concepts. LONG DESCRIPTION SYNTAX get-help {<CmdletName> | <TopicName>} help {<CmdletName> | <TopicName>} <CmdletName> -? "Get-help" and "-?" display help on one page. "Help" displays help on multiple pages. Examples: get-help get-process : Displays help about the Get-Process cmdlet. get-help about_signing : Displays help about signing scripts. help where-object : Displays help about the Where-Object cmdlet. help about_foreach : Displays help about foreach loops in PowerShell. set-service -? : Displays help about the Set-Service cmdlet. You can use wildcard characters in the help commands (not with -?). If multiple help topics match, PowerShell displays a list of matching topics. If only one help topic matches, PowerShell displays the topic. Examples: get-help * : Displays all help topics. get-help get-* : Displays topics that begin with get-. help *object* : Displays topics with "object" in the name. get-help about* : Displays all conceptual topics. For information about wildcards, type: get-help about_wildcard REMARKS To learn about Windows PowerShell, read the following help topics: get-command : Gets information about cmdlets from the cmdlet code. get-member : Gets the properties and methods of an object. where-object : Filters object properties. about_object : Explains the use of objects in Windows PowerShell. about_remote : Tells how to run commands on remote computers. Conceptual help files are named "about_<topic>", such as: about_regular_expression. The names of conceptual help files must be entered in English even on non-English versions of Windows PowerShell. The help commands also display the aliases of the cmdlets. These are alternate names or nicknames that are often easier to type. For example, the alias for the Invoke-Command cmdlet is "remote". To get the aliases, type: get-alias PS M:\> """# 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