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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

@"""
"""
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(\[|){\n(?<tab> )"id": "[0-9]*",\n\<tab>"type": [0-9],\n\<tab>"content": "[^"]*",\n\<tab>"channel_id": "[0-9]*",\n\<tab>"author": {\n(?<dtab> )"id": "[^"]*",\n\<dtab>"username": "[^"]*",\n\<dtab>"avatar": "[^"]*",\n\<dtab>"discriminator": "([0-9]{4}|[0-9])",\n\<dtab>"public_flags": [0-9]*,\n\<dtab>"flags": [0-9]*,\n\<dtab>"banner": (null|"[0-9]*"),\n\<dtab>"accent_color": (null|"[^"]*"),\n\<dtab>"global_name": "[^"]*",\n\<dtab>"avatar_decoration_data": (null|"[^"]*"),\n\<dtab>"banner_color": (null|"[^"]*")\n\<tab>},\n\<tab>"attachments": \[[^\]]*\],\n\<tab>"embeds": \[[^\]]*],\n\<tab>"mentions": \[[^\]]*],\n\<tab>"mention_roles": \[[^\]]*\],\n\<tab>"pinned": (true:|false),\n\<tab>"mention_everyone": (true|false),\n\<tab>"tts": (true:|false),\n\<tab>"timestamp": "[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{6}\+[0-9]{2}:[0-9]{2}",\n\<tab>"edited_timestamp": (null|"[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{6}\+[0-9]{2}:[0-9]{2}"),\n\<tab>"flags": [0-9]*,\n\<tab>"components": \[[^\]]*]\n}(\]|\,|)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" { "id": "1145344233713188874", "type": 0, "content": "913 - this icecream good", "channel_id": "1124414874454339715", "author": { "id": "746383273621717104", "username": "kalote.", "avatar": "95b9bdc7aa5784a2354e2ec5256ae736", "discriminator": "0", "public_flags": 128, "flags": 128, "banner": null, "accent_color": null, "global_name": "Carrot :3", "avatar_decoration_data": null, "banner_color": null }, "attachments": [], "embeds": [], "mentions": [], "mention_roles": [], "pinned": false, "mention_everyone": false, "tts": false, "timestamp": "2023-08-27T13:09:04.784000+00:00", "edited_timestamp": null, "flags": 0, "components": [] }, """# 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