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

/
/
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 = "(\${1,2})[^]*?[^\\]\1|[^\$]+" Local $sString = "some text outside $ \$2+\$ $ which includes $\$$" & @CRLF & _ "Now some $${}$$ $\{\}$inline mathjax $2+2$" & @CRLF & _ "And in new lines" & @CRLF & _ "$$" & @CRLF & _ "2+2" & @CRLF & _ "$$" & @CRLF & _ "$" & @CRLF & _ "2+2\\" & @CRLF & _ "3+3\\" & @CRLF & _ " 4+4\\" & @CRLF & _ "$" & @CRLF & _ "more inline $2+2\$ \$2+2$ $2+2$, $3+4$" & @CRLF & _ "separated $2+2$ by some text $ 2+2 $ again" & @CRLF & _ "double newlines" & @CRLF & _ "$2+2$" & @CRLF & _ "$2+2$" & @CRLF & _ "Dollar again $ \$42 $" & @CRLF & _ "$$ \$42 $$" & @CRLF & _ "$$" & @CRLF & _ " \frac{4}{2}+" & @CRLF & _ " \frac{4}{2}" & @CRLF & _ "$$" & @CRLF & _ "" & @CRLF & _ "And some more tests:" & @CRLF & _ "\> a) $\dr{1}{2}+\left(\dr23-\dr34\right)$<<<" & @CRLF & _ " \> b) $\dr{1}{5}+\left(\dr23-\dr12\right)$<<<" & @CRLF & _ " \> c) $\dr{1}{2}+\left(\dr{3}{4}-\dr32\right)$<<<" & @CRLF & _ " \> d) $\left(\dr{3}{10}-\dr{5}{2}\right)+\dr7{20}$<<<" & @CRLF & _ " \> e) $\dr{2}{3}+\left(\dr{3}{2}-\dr14\right)$<<<" & @CRLF & _ " \> f) $\left(\dr{14}{5}-\dr7{10}\right)+\dr{11}{10}$.<<<" & @CRLF & _ "" & @CRLF & _ "$$" & @CRLF & _ " a^{\rr mn}=\sq[n]{a^m}." & @CRLF & _ "$$" & @CRLF & _ "" & @CRLF & _ "$$" & @CRLF & _ "\begin{align}" & @CRLF & _ "&a^x\cdot a^y=a^{x+y}\\" & @CRLF & _ "&\dr{a^x}{a^y}=a^{x-y}\\" & @CRLF & _ "&(a^x)^y=a^{xy}\\" & @CRLF & _ "&(ab)^x=a^xb^x\\" & @CRLF & _ "&\left(\dr ab\right)^x=\dr{a^x}{b^x}." & @CRLF & _ "\end{align}" & @CRLF & _ "$$" & @CRLF & _ "" & @CRLF & _ "$$" & @CRLF & _ " \sq[4]{5\sq5}=(5\sq5)^{\rr14}=(5\.5^{\rr12})^{\rr14}=" & @CRLF & _ " (5^{1+\rr12})^{\rr14}=(5^{\rr32})^{\rr14}=5^{\rr38}." & @CRLF & _ " $$" & @CRLF & _ "" & @CRLF & _ "Hope that's it." & @CRLF & _ "" & @CRLF & _ "" & @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