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"
"

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(\{(?:.|\n)*\})"# let regex = try! NSRegularExpression(pattern: pattern) let testString = ##""" // API callback google.search.Search.apiary2387({ "cursor": { "currentPageIndex": 0, "estimatedResultCount": "4490", "moreResultsUrl": "http://www.google.com/cse?oe=utf8&ie=utf8&source=uds&q=ssh&start=0&sort=&cx=013305635491195529773:0ufpuq-fpt0", "resultCount": "4,490", "searchResultTime": "0.22", "pages": [ { "label": 1, "start": "0" }, { "label": 2, "start": "1" }, { "label": 3, "start": "2" }, { "label": 4, "start": "3" }, { "label": 5, "start": "4" }, { "label": 6, "start": "5" }, { "label": 7, "start": "6" }, { "label": 8, "start": "7" }, { "label": 9, "start": "8" }, { "label": 10, "start": "9" } ] }, "context": { "title": "Pastebin Active", "total_results": "0", "facets": [] }, "results": [ { "GsearchResultClass": "GwebSearch", "cacheUrl": "http://www.google.com/search?q=cache:PBL2A25kpZoJ:pastebin.com", "clicktrackUrl": "https://www.google.com/url?q=http://pastebin.com/u/ssh&sa=U&ved=0ahUKEwiO4fjNpovMAhWBPxoKHYJXAS4QFggEMAA&client=internal-uds-cse&usg=AFQjCNHczEhDXdcUnRZhpArEeSiHfjwMJA", "content": "BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\n. SIGN UP takes 10 seconds, and it&#39;s free! Guest&nbsp;...", "contentNoFormatting": "BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\n. SIGN UP takes 10 seconds, and it's free! Guest ...", "formattedUrl": "pastebin.com/u/\u003cb\u003essh\u003c/b\u003e", "title": "\u003cb\u003eSsh&#39;s\u003c/b\u003e Pastebin - Pastebin.com", "titleNoFormatting": "Ssh's Pastebin - Pastebin.com", "unescapedUrl": "http://pastebin.com/u/ssh", "url": "http://pastebin.com/u/ssh", "visibleUrl": "pastebin.com", "richSnippet": { "cseImage": { "src": "http://pastebin.com/i/facebook.png" }, "metatags": { "fbAppId": "231493360234820", "ogTitle": "Ssh's Pastebin - Pastebin.com", "ogType": "article", "ogUrl": "http://pastebin.com/u/ssh", "ogImage": "http://pastebin.com/i/facebook.png", "ogSiteName": "Pastebin", "viewport": "width=device-width, maximum-scale=1.0, user-scalable=no" } } } ] } ); """## 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