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

/
/
xig

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #""" (?={)(?(DEFINE) (?<number> [0-9]+(?:\.[0-9]*)?(?:e[+-]?[0-9]+)?) (?<string> \\" (?>[^"\\]+|\\\\(?:[^\\]|\\.))* \\" ) (?<boolean> true | false | null) (?<pair> (?: \g<string> | \g<number>) \s* : \s* (?: \g<string> | \g<number> | \g<boolean> | \g<json> | \g<array> ) ) (?<array> \[\s* \g<json> (?: \s*,\s* \g<json>)* \s*]) (?<json> { \s* \g<pair> (?:\s*,\s* \g<pair>)* }) ) \g<json> """# let regex = try! NSRegularExpression(pattern: pattern, options: [.caseInsensitive, .allowCommentsAndWhitespace]) let testString = #""b<---------------->{\"status\":\"ok\",\"plugin_version\":\"1.2.6\",\"post\":{\"id\":7598,\"type\":\"post\",\"slug\":\"honeycrisp-apple-sangria-recipe\",\"url\":\"http:\\/\\/www.bigbigbutts.com\\/2013\\/08\\/honeycrisp-apple-sangria-recipe\\/\",\"status\":\"publish\",\"title\":\"Honeycrisp Apple Sangria Recipe\",\"title_plain\":\"Honeycrisp Apple Sangria Recipe\",\"content\":\"<div class=\\\"pin-it-btn-wrapper\\\"><a href=\\\"\\/\\/www.pinterest.com\\/pin\\/create\\/button\\/?url=http%3A%2F%2Fwww.bigbigbutts.com%2F2013%2F08%2Fhoneycrisp-apple-sangria-recipe%2F&media=http%3A%2F%2Fwww.bigbigbutts.com%2Fwp-content%2Fuploads%2F2013%2F08%2Fhoneycrisp-apple-sangria.jpg&description=Honeycrisp%20Apple%20Sangria%20Recipe\\\" data-pin-do=\\\"buttonBookmark\\\" data-pin-config=\\\"none\\\" rel=\\\"nobox\\\"><\\/a><\\/div>\",\"raw_content\":\"\",\"excerpt\":\"\",\"date\":\"2013-08-24T11:18:07+00:00\",\"modified\":\"2014-04-24T09:45:00+00:00\",\"author\":{\"id\":2,\"slug\":\"gia\",\"name\":\"gia\",\"first_name\":\"gia\",\"last_name\":\"Wenner chia\",\"nickname\":\"gia\",\"url\":\"http:\\/\\/giawennerchia.com\",\"description\":\"gia Wenner chia is a writer and mom who gets paid to obsess over Pinterest and blogs for Ahalogy, a Cincinnati-based startup. She lives in her hometown of West Chester, Ohio, with her husband, two young children, and their dog.\"},\"attachments\":[{\"id\":7599,\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"slug\":\"honeycrisp-apple-sangria\",\"title\":\"honeycrisp-apple-sangria\",\"description\":\"\",\"caption\":\"\",\"parent\":7598,\"mime_type\":\"image\\/jpeg\",\"images\":{\"full\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"width\":580,\"height\":406},\"thumbnail\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-150x150.jpg\",\"width\":150,\"height\":150},\"medium\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-300x210.jpg\",\"width\":300,\"height\":210},\"large\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"width\":580,\"height\":406},\"Mini Square\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-70x70.jpg\",\"width\":70,\"height\":70},\"Square\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-115x115.jpg\",\"width\":115,\"height\":115},\"Featured Tabs\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-150x225.jpg\",\"width\":150,\"height\":225}}}],\"featured_image\":{\"id\":7599,\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"slug\":\"honeycrisp-apple-sangria\",\"title\":\"honeycrisp-apple-sangria\",\"description\":\"\",\"caption\":\"\",\"parent\":7598,\"mime_type\":\"image\\/jpeg\",\"images\":{\"full\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"width\":580,\"height\":406},\"thumbnail\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-150x150.jpg\",\"width\":150,\"height\":150},\"medium\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-300x210.jpg\",\"width\":300,\"height\":210},\"large\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria.jpg\",\"width\":580,\"height\":406},\"Mini Square\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-70x70.jpg\",\"width\":70,\"height\":70},\"Square\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-115x115.jpg\",\"width\":115,\"height\":115},\"Featured Tabs\":{\"url\":\"http:\\/\\/www.bigbigbutts.com\\/wp-content\\/uploads\\/2013\\/08\\/honeycrisp-apple-sangria-150x225.jpg\",\"width\":150,\"height\":225}}}}}<random shit><dafkdjkfjdaksf""# 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