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

/
/
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)((?<==\h)\([A-Z][A-Z0-9_]+\b(?=[<:\;])|\b(?<!<)[A-Z][A-Z0-9_]+(?=[^>\)]))\b|\b((?<!=\s)(?<!\.)[A-Z]+\d*?(?![\(\;:])(?=[,\)>\s]))\b" Local $sString = "This still has a problem with FOUR+ character match " & @CRLF & _ "\b(?<!val\s)(?<!var\s)(?<!=)(?<!=\s)(?<!\.)([A-Z]{1,3}[0-9]*?)\b" & @CRLF & _ "\b(?<!val\s|var\s|=|=\s|\.)([A-Z]+|[A-Z0-9]+)\b" & @CRLF & _ "\b([A-Z0-9]{1,3})\b(?![\(;:])(?=[,\)> ])" & @CRLF & _ "<[A-Z0-9]+>|\([A-Z0-9]+\)" & @CRLF & _ "\b([A-Z0-9]{1,3})\b" & @CRLF & _ "" & @CRLF & _ "<in T, out R>" & @CRLF & _ ": R {" & @CRLF & _ ": R =" & @CRLF & _ "(S, T, R)" & @CRLF & _ "(S)" & @CRLF & _ "-> S" & @CRLF & _ "-> (S)" & @CRLF & _ "" & @CRLF & _ "[^a-z:\s\.\,]" & @CRLF & _ "" & @CRLF & _ "<>" & @CRLF & _ ":\w+(?=,|>)" & @CRLF & _ "" & @CRLF & _ "//-------------------" & @CRLF & _ "" & @CRLF & _ "class IO<out A>(val fn: () -> A) { // blows the stack" & @CRLF & _ " fun <B> map(g: (A) -> B): IO<B> = IO { g(this()) }" & @CRLF & _ " fun <B> flatMap(g: (A) -> IO<B>): IO<B> = IO { g(this())() }" & @CRLF & _ "" & @CRLF & _ " operator fun invoke(): A = fn()" & @CRLF & _ "" & @CRLF & _ " companion object {" & @CRLF & _ " val empty: IO<Unit> = IO {}" & @CRLF & _ " operator fun <A> invoke(a: A): IO<A> = IO { a }" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "// blows the stack" & @CRLF & _ "fun <A, B> forever(ioa: IO<A>): IO<B> {" & @CRLF & _ " val t: () -> IO<B> = { forever(ioa) }" & @CRLF & _ " return ioa.flatMap { t() }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "var count = 0" & @CRLF & _ "val program: IOU = IO {" & @CRLF & _ " forever<String, String>(IO { "${count++} Repeating function" })" & @CRLF & _ " .flatMap { Console.println(it) }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "//-----------------------" & @CRLF & _ "" & @CRLF & _ "class State<S, out T>(val runState: (S) -> Pair<S, T>) {" & @CRLF & _ "" & @CRLF & _ " fun <R> map(f: (T) -> R): State<S, R> =" & @CRLF & _ " flatMap { t -> pure<S, R>(f(t)) }" & @CRLF & _ "" & @CRLF & _ " fun <P15, R> map(sx: State<S, P1>, f: (T, P1) -> R): State<STAB, R> =" & @CRLF & _ " flatMap { t -> sx.map { x -> f(t, x) } }" & @CRLF & _ "" & @CRLF & _ " fun <R> flatMap(f: (T) -> State<S, R>): State<S, R> =" & @CRLF & _ " State { s ->" & @CRLF & _ " val (s1, t) = runState(s)" & @CRLF & _ " f(t).runState(s1)" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " companion object {" & @CRLF & _ " fun <S, T> pure(t: T): State<S, T> =" & @CRLF & _ " State { s -> s to t }" & @CRLF & _ "" & @CRLF & _ " fun <S> get(): State<S, S> =" & @CRLF & _ " State { s -> s to s }" & @CRLF & _ "" & @CRLF & _ " fun <S> set(newState: S): State<S, Unit> =" & @CRLF & _ " State { _ -> newState to Unit }" & @CRLF & _ "" & @CRLF & _ " fun <S> modify(f: (S) -> S): State<S, Unit> =" & @CRLF & _ " get<S>().flatMap { s: S -> set(f(s)).map { Unit } }" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "//----------------" & @CRLF & _ "" & @CRLF & _ "data class Book(" & @CRLF & _ " val ISDN: String," & @CRLF & _ " val name: String," & @CRLF & _ " val pages: Int," & @CRLF & _ " val price: Price," & @CRLF & _ " val weight: Double," & @CRLF & _ " val year: Int," & @CRLF & _ " val author: String" & @CRLF & _ ")" & @CRLF & _ "" & @CRLF & _ "//-------------------" & @CRLF & _ "" & @CRLF & _ "fun <S, A> StateAlias<S, A>.map(f: (A) -> Boolean): StateAlias<S, Boolean> =" & @CRLF & _ " { s ->" & @CRLF & _ " val (s1, t) = this(s)" & @CRLF & _ " when {" & @CRLF & _ " f(s1) -> Pair(true, t)" & @CRLF & _ " else -> Pair(false, t)" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ "fun <S, A, B> flatMap(): ((StateAlias<S, A>) -> (A)) -> ((A) -> (StateAlias<S, B>)) -> StateAlias<S, B>" & @CRLF & _ "" & @CRLF & _ "//--------------------" & @CRLF & _ "" & @CRLF & _ "val dog = Dog(id = 0, name = "Doglin", furColour = FurColour.BLACK" & @CRLF & _ "" & @CRLF & _ "val cat: DOG = DOG" & @CRLF & _ "" & @CRLF & _ "//-------------------" & @CRLF & _ "" & @CRLF & _ "fun <T : Comparable<T>> sort(list: List<T>)" & @CRLF & _ "" & @CRLF & _ "fun <T> cloneWhenGreater(list: List<T>, threshold: T): List<T>" & @CRLF & _ " where T : Comparable," & @CRLF & _ " T : Cloneable {" & @CRLF & _ " return list.filter { it > threshold }.map { it.clone() }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "//----------------------" & @CRLF & _ "" & @CRLF & _ "enum class FurColour { BLACK, GREEN, PATCHED; }" & @CRLF & _ "" & @CRLF & _ "enum class Direction {" & @CRLF & _ " NORTH, SOUTH, WEST, EAST" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "enum class Color(val rgb: Int) {" & @CRLF & _ " RED(0xFF0000)," & @CRLF & _ " GREEN(0x00FF00)," & @CRLF & _ " BLUE(0x0000FF)" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "enum class ProtocolState {" & @CRLF & _ " WAITING {" & @CRLF & _ " override fun signal() = TALKING" & @CRLF & _ " }," & @CRLF & _ "" & @CRLF & _ " TALKING {" & @CRLF & _ " override fun signal() = WAITING" & @CRLF & _ " };" & @CRLF & _ "" & @CRLF & _ " abstract fun signal(): ProtocolState" & @CRLF & _ "}" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm