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){tex\b([^{}]*({[^{}]*?([^{}]|(?R))*[^{}]*?}[^{}]*)*[^{}]*)}" Local $sString = "# This is currently a test" & @CRLF & _ "" & @CRLF & _ "{nav Home}" & @CRLF & _ "" & @CRLF & _ "The statistical model estimated the probability, {tex f(x) = \int_{-\infty}" & @CRLF & _ "^\infty \hat f(\xi)\,e^{2 \pi \xi x} \,d\xi }, of capturing dolphins on a tow, {tex i}. A year effect, {tex \lambda_{acb_{j}}} was estimated for each year, {tex j}, allowing for annual variation in the capture event rates that was unrelated to the covariates, {tex x}. The contribution of each covariate, indexed by {tex c}, was governed by a regression coefficient, {tex \beta_c}, that was estimated by the model. The logit transform of the capture event probability was defined as the sum of the year effect, {tex \lambda_{lam} {lam} }, and the covariates:" & @CRLF & _ "{tex \lambda_{lam}{lam} }" & @CRLF & _ "{tex \lambda_{lam} {lam} }" & @CRLF & _ "{tex \lambda_{lam}{lam}}" & @CRLF & _ "katex {{{" & @CRLF & _ "logit(\pi_i) = \lambda_{j[i]} + \sum_c \beta_c x_{ic}." & @CRLF & _ "}}}" & @CRLF & _ "determines the result." & @CRLF & _ "" & @CRLF & _ "# The following is more tests" & @CRLF & _ "" & @CRLF & _ "katex {{{" & @CRLF & _ "f(x) = \int_{-\infty}^\infty" & @CRLF & _ " \hat f(\xi)\,e^{2 \pi i \xi x}" & @CRLF & _ " \,d\xi " & @CRLF & _ "}}}" & @CRLF & _ "" & @CRLF & _ "katex {{{" & @CRLF & _ "\begin{bmatrix}" & @CRLF & _ " a & b \\" & @CRLF & _ " c & a " & @CRLF & _ " \end{bmatrix}" & @CRLF & _ "}}}" & @CRLF & _ "" & @CRLF & _ "katex {{{" & @CRLF & _ "\begin{bmatrix}" & @CRLF & _ " a & c \\" & @CRLF & _ " c & a " & @CRLF & _ " \end{bmatrix}" & @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