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

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)(^\s+_[A-Za-z]+\._)" Local $sString = "was from an authentic copy, and a careful comparison of the text with" & @CRLF & _ "the earlier one shows that in the meantime the play "underwent revision," & @CRLF & _ "received some slight augmentation, and in some few places must have been" & @CRLF & _ "entirely rewritten." A marked instance of this rewriting--the only one" & @CRLF & _ "of considerable length--is in ii. 6. 6-37, where the first quarto reads" & @CRLF & _ "thus (spelling and pointing being modernized):--" & @CRLF & _ "" & @CRLF & _ " _Jul._ Romeo." & @CRLF & _ "" & @CRLF & _ " _Rom._ My Juliet, welcome. As do waking eyes" & @CRLF & _ " Closed in Night's mists attend the frolick Day," & @CRLF & _ " So Romeo hath expected Juliet," & @CRLF & _ " And thou art come." & @CRLF & _ "" & @CRLF & _ " _Jul._ I am, if I be Day," & @CRLF & _ " Come to my Sun: shine forth and make me fair." & @CRLF & _ "" & @CRLF & _ " _Rom._ All beauteous fairness dwelleth in thine eyes." & @CRLF & _ "" & @CRLF & _ " _Jul._ Romeo, from thine all brightness doth arise." & @CRLF & _ "" & @CRLF & _ " _Fri._ Come, wantons, come, the stealing hours do pass," & @CRLF & _ " Defer embracements till some fitter time." & @CRLF & _ " Part for a while, you shall not be alone" & @CRLF & _ " Till holy Church have joined ye both in one." & @CRLF & _ "" & @CRLF & _ " _Rom._ Lead, holy Father, all delay seems long." & @CRLF & _ "" & @CRLF & _ " _Jul._ Make haste, make haste, this lingering doth us wrong." & @CRLF & _ "" & @CRLF & _ "For convenient comparison I quote the later text here:--" & @CRLF & _ "" & @CRLF & _ " _Juliet._ Good even to my ghostly confessor." & @CRLF & _ "" & @CRLF & _ " _Friar Laurence._ Romeo shall thank thee, daughter, for us both." & @CRLF & _ "" & @CRLF & _ " _Juliet._ As much to him, else is his thanks too much." & @CRLF & _ "" & @CRLF & _ " _Romeo._ Ah, Juliet, if the measure of thy joy" & @CRLF & _ " Be heap'd like mine and that thy skill be more" & @CRLF & _ " To blazon it, then sweeten with thy breath" & @CRLF & _ " This neighbour air, and let rich music's tongue" & @CRLF & _ " Unfold the imagin'd happiness that both" & @CRLF & _ " Receive in either by this dear encounter." & @CRLF & _ "" & @CRLF & _ " _Juliet._ Conceit, more rich in matter than in words," & @CRLF & _ " Brags of his substance, not of ornament." & @CRLF & _ " They are but beggars that can count their worth;" & @CRLF & _ " But my true love is grown to such excess" & @CRLF & _ " I cannot sum up half my sum of wealth." & @CRLF & _ "" & @CRLF & _ " _Friar Laurence._ Come, come with me, and we will make short work;" & @CRLF & _ " For, by your leaves, you shall not stay alone" & @CRLF & _ " Till holy church incorporate two in one." & @CRLF & _ "" & @CRLF & _ "The "omission, mutilation, or botching" by which some German editors" & @CRLF & _ "would explain all differences between the earlier and later texts will" & @CRLF & _ "not suffice to account for such divergence as this. "The two dialogues" & @CRLF & _ "do not differ merely in expressiveness and effect; they embody different" & @CRLF & _ "conceptions of the characters;" and yet we cannot doubt that both were" & @CRLF & _ "written by Shakespeare." & @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