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

/
/
uig

Test String

Code Generator

Language

Generated Code

import Foundation // WARNING: You included a flag that Swift doesn't support: u // When this flag is set, it makes the pattern and subject strings to be treated as unicode. // Swift already treats the pattern and subject strings as unicode by default, so including this flag is redundant. let pattern = ##"{\s*{\s*#\s*(?<operator>endcase|endswitch|endfor|endif|if|elif|else|for|switch|case|default)\s*(?<args>[^}]*)\s*}\s*}\s*(?<body>[^{]*(?:\s*{\s*{\s*#\s*(?!(?&operator))\s*[^}]*\s*}\s*}\s*[^{]*)*)"## let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive) let testString = ##""" <div> {{#if arg1.arg2}} <span>{{#var arg3 static}}</span> blablabla{{#for k, v in arg4}} <p>{{#var k}}<span>{{#var v.arg5}}</span></p> {{#if (k == "test" or v != 0) and k == 0}} <span></span> {{#elif k == 0}} <p></p> {{#else}} <div></div> {{#endif}} {{#endfor}} {{#endif}} {{#switch arg6}} {{#case 5}} case 5 {{#case 6, 7, 8}} case 6, 7, 8 {{#endcase}} {{#default}} def {{#endcase}} {{#endswitch}} {{#for i as 0, 5}} test i {{#endfor}} """## 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