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

r'''
'''
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(│?\s{3,})*[├└]─{2} "# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" ├── Blog │ └── _v_images ├── Essay │ └── Encryption&Trust ├── Hidden │ └── _v_images ├── Life │ ├── Cuisine │ ├── Game │ ├── Ideas │ ├── Linguistic │ │ └── English │ └── Music ├── Other │ └── _v_images ├── PWN │ └── _v_images ├── Programme │ └── _v_images ├── Work │ ├── Database │ ├── GUI │ │ └── CSS │ ├── Language │ │ └── DocString │ │ └── __pycache__ │ ├── Network │ ├── OS │ │ ├── Android │ │ │ ├── BuildTools │ │ │ ├── DevTools │ │ │ ├── Permissions │ │ │ ├── PropertiesLogs │ │ │ ├── Signer │ │ │ │ ├── META-INF │ │ │ │ └── webview │ │ │ │ ├── META-INF │ │ │ │ ├── assets │ │ │ │ │ └── stored-locales │ │ │ │ │ └── weblayer │ │ │ │ ├── lib │ │ │ │ │ ├── arm64-v8a │ │ │ │ │ └── armeabi-v7a │ │ │ │ └── res │ │ │ │ ├── anim │ │ │ │ ├── anim-v21 │ │ │ │ ├── animator │ │ │ │ ├── animator-v21 │ │ │ │ ├── color │ │ │ │ ├── color-v21 │ │ │ │ ├── color-v23 │ │ │ │ ├── drawable │ │ │ │ ├── drawable-hdpi-v4 │ │ │ │ ├── drawable-ldrtl-hdpi-v17 │ │ │ │ ├── drawable-ldrtl-v17 │ │ │ │ ├── drawable-ldrtl-xhdpi-v17 │ │ │ │ ├── drawable-ldrtl-xxhdpi-v17 │ │ │ │ ├── drawable-ldrtl-xxxhdpi-v17 │ │ │ │ ├── drawable-night-hdpi-v8 │ │ │ │ ├── drawable-night-v8 │ │ │ │ ├── drawable-night-xhdpi-v8 │ │ │ │ ├── drawable-night-xxhdpi-v8 │ │ │ │ ├── drawable-night-xxxhdpi-v8 │ │ │ │ ├── drawable-v21 │ │ │ │ ├── drawable-v23 │ │ │ │ ├── drawable-v4 │ │ │ │ ├── drawable-xhdpi-v4 │ │ │ │ ├── drawable-xxhdpi-v4 │ │ │ │ ├── drawable-xxxhdpi-v4 │ │ │ │ ├── font │ │ │ │ ├── interpolator │ │ │ │ ├── interpolator-v21 │ │ │ │ ├── layout │ │ │ │ ├── layout-land │ │ │ │ ├── layout-v21 │ │ │ │ ├── layout-v22 │ │ │ │ ├── layout-v26 │ │ │ │ ├── menu │ │ │ │ ├── raw │ │ │ │ └── xml │ │ │ └── UID │ │ └── Linux │ ├── Presentation │ │ ├── Diagram │ │ ├── Slides │ │ │ └── images │ │ └── Writing │ ├── Project │ ├── RE │ ├── Service │ ├── Tool │ │ ├── Diff │ │ ├── File │ │ ├── Frida │ │ │ └── scripts │ │ ├── Git │ │ ├── IO │ │ ├── Shell │ │ └── Text │ └── Virtualization │ └── Docker └── 随笔 └── _v_images """# 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