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

/
/
g

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 $sRegex = "(\$[^\n$]*[^\s$])(-|=|\+)([^\s$][^\n$]*\$)" Local $sString = "\end{theorem}" & @CRLF & _ "" & @CRLF & _ " A $k$-periodic sequence has the property that $s_i = s_{i + k}$ for all $i = 0,1,\dots$." & @CRLF & _ " Thus a $k$-periodic sequence $(s_i)_{i = 0}^\infty$ may be represented by any finite sequence $(s_i)_{i=a}^{a+k - 1}$, where $a$ is usually chosen to be $0$." & @CRLF & _ " " & @CRLF & _ " Sadly our Fibonacci sequence examples are not defined over a finite field but over the naturals and thus are not necessarily periodic." & @CRLF & _ " Examples such as these may be interpreted to have a period of $\infty$. " & @CRLF & _ " " & @CRLF & _ " The period and related stability of linear recurrence sequences in regard to linear complexity has a very rich and broadly studied background~\cite{DingZiaoShan1991}." & @CRLF & _ " " & @CRLF & _ " \begin{theorem}" & @CRLF & _ " \label{th: max period is m-sequence}" & @CRLF & _ " \cite[Theorem~6.33]{LidlNiederreiter1994}" & @CRLF & _ " A linear recurrence sequence $s$ over a finite field $\gf_2$ with linear complexity $n$ has a maximum possible period of $2^n-1$." & @CRLF & _ " \end{theorem}" & @CRLF & _ " " & @CRLF & _ " \begin{definition}" & @CRLF & _ " \label{de: m-sequence}" & @CRLF & _ " A sequence which has maximum period for giv" 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