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

/
/
gmx

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #""" (?|(?:\G(?!\A)(?<=\|)|^\|\h*\[x\]\h*\|)\h*\K([^|\n]+)(?<=\S)\h*\||\[x]\h*\K([^|\s!]+(?:\h*[^|\s]+)*))| (?|(?:\G(?!\A)\||^\|\h*\[x]\h*!\h*\|)\h*\K([^|\n]+)(?<=\S)\h*|\[x]\h*!\h*\K([^|\s]+(?:\h*[^|\s]+)*)) """# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace]) let testString = #""" Test cases where it should match. - [x] Example task. | Task ends. [x] Another task. - [x] ! Example task. | This ends. [x] ! Another task. - [x] Example task! | Task ends. [x] Another task! - [x] ! Example task! | This ends. [x] ! Another task! This is a sentence. [x] Task is here. Other text. Another [x] ! Task is here. Must not match in the table. | | Task name | Plan | Actual | File | | :---- | :-------------| :---------: | :---------: | :------------: | | [x] | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] | | [x] ! | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] | Groups expected: $1: all text after [x] $2: all text after [x] ! Regex for each group: $1: [^\|\s]\s*\[x\]\s*\K[^!|\n]* $2: [^\|\s]\s*\[x\]\s*\!\s*\K[^|\n]* With the not-capturing group applied: $1: (?:[^\|\s]\s*\[x\]\s*\K[^!|\n]*) $2: (?:[^\|\s]\s*\[x\]\s*\!\s*\K[^|\n]*) The combined expression: (?:[^\|\s]\s*\[x\]\s*\K([^!|\n]*))|(?:[^\|\s]\s*\[x\]\s*\!\s*\K([^|\n]*)) """# 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