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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?s)(Object(?:(?!Object).)*?ByteCode[ \t]*:[ \t]*\R+)((?:(?:(?!EndByteCode).)*?(?:(?(3)(?!))(\b\w*?z\b)|(?(4)(?!))(?!\3\b)(\b\w*?z\b)|(?(5)(?!))(?!\b(?:\3|\4)\b)(\b\w*?z\b)|(?(6)(?!))(?!\b(?:\3|\4|\5)\b)(\b\w*?z\b)|(?(7)(?!))(?!\b(?:\3|\4|\5|\6)\b)(\b\w*?z\b)|(?(8)(?!))(?!\b(?:\3|\4|\5|\6|\7)\b)(\b\w*?z\b)|(?(9)(?!))(?!\b(?:\3|\4|\5|\6|\7|\8)\b)(\b\w*?z\b))){1,7})"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" BEFORE: Object Type : InfinityProgram LastChange : 2/18/2025 5:15:38 PM DeviceId : NetWork_MankatoO\OfcDmp\Vav5_26 Alias : RmTempSignalPRG CreateTime : 2/18/2025 5:13:20 PM CreatedBy : Root\Acc TimeLocked : 2/18/2025 5:15:38 PM InstanceId : 7227/33 ByteCode : 'ROOM TEMPERATURE CONTROL SIGNAL CALCULATIONS ' Dylan Salisbury Paape Energy Services 5/19/23 Numeric sync, lasthour Numeric actn ' control loop "action" 1 or 0 (direct or reverse) Line StartUp Goto RmHappy Line RmHappy If ((IntrLkSystemRun = On) & (TempRmAvg > (StptRoom + 1)) & (TS > 2)) then Goto RmWarm TempRmCntrlSig = 50 DamperPositionz = .5 Line RmWarm If ((IntrLkSystemRun = Off) or (TempRmAvg < StptRoom)) then Goto RmHappy TempRmCntrlSigz = PID11Fct(TempRmAvg, StptRoom, PIDTR[1], PIDTR[2], PIDTR[3], 0.5, actn, PIDTR[4], PIDTR[5], 0.5, 1, TempRmCntrlSigz, 0.005, Date) TempRmCntrlSig = (TempRmCntrlSigz * 100) DamperPositionz = .25 TempRmCntrlSigzAAAz = XXX EndByteCode Status : Active EndObject """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"$1Numeric $3, $4, $5, $6, $7, $8, $9\r\n\r\n$2"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) 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