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 $sRegex = " *(?:.*\S.*\n)+\n? *: +(?:.|\n)+?(?:\n{2,}(?=\S)(?! *: +)(?! *(?:\S.*\n)+?\n? *: +)|$)" Local $sString = "=== Single <dt> and <dd>" & @CRLF & _ "" & @CRLF & _ "GitHub" & @CRLF & _ ": a site where over 73 million developers shape the future of software, together" & @CRLF & _ "" & @CRLF & _ "=== Multiple <dt>-<dd> group" & @CRLF & _ "" & @CRLF & _ "Firefox" & @CRLF & _ ": a free, open source, cross-platform, graphical web browser developed by the Mozilla Corporation and hundreds of volunteers" & @CRLF & _ "" & @CRLF & _ "MDN" & @CRLF & _ ": provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps" & @CRLF & _ "" & @CRLF & _ "=== Single <dt> with multiple <dd>s" & @CRLF & _ "" & @CRLF & _ "Apple" & @CRLF & _ " : an American multinational technology company that specializes in consumer electronics, computer software and online services." & @CRLF & _ " : an edible fruit produced by an apple tree" & @CRLF & _ "" & @CRLF & _ "=== Multiple <dt>s" & @CRLF & _ "" & @CRLF & _ "Windows" & @CRLF & _ "Microsoft Windows" & @CRLF & _ "Win" & @CRLF & _ ": a group of several proprietary graphical operating system families, all of which are developed and marketed by Microsoft" & @CRLF & _ "" & @CRLF & _ "=== separated by blank lines" & @CRLF & _ "" & @CRLF & _ "Solaris" & @CRLF & _ "" & @CRLF & _ ": a 1961 science fiction novel by Polish writer Stanisław Lem" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ ": a proprietary Unix operating system originally developed by Sun Microsystems" & @CRLF & _ "" & @CRLF & _ "=== <dd>s with inline breaks" & @CRLF & _ "" & @CRLF & _ "Oracle" & @CRLF & _ ": an American multinational computer technology" & @CRLF & _ "corporation headquartered in Austin, Texas" & @CRLF & _ "" & @CRLF & _ ": the priest or priestess uttering the prediction," & @CRLF & _ "may also refer to the site of the oracle" & @CRLF & _ "" & @CRLF & _ "===" & @CRLF & _ "" & @CRLF & _ "😂" & @CRLF & _ ": 😂 face with tears of joy" & @CRLF & _ "" & @CRLF & _ "===" & @CRLF & _ "" & @CRLF & _ "Term 1" & @CRLF & _ "" & @CRLF & _ ": This is a definition with two paragraphs. Lorem ipsum " & @CRLF & _ " dolor sit amet, consectetuer adipiscing elit. Aliquam " & @CRLF & _ " hendrerit mi posuere lectus." & @CRLF & _ "" & @CRLF & _ " Vestibulum enim wisi, viverra nec, fringilla in, laoreet" & @CRLF & _ " vitae, risus." & @CRLF & _ "" & @CRLF & _ ": Second definition for term 1, also wrapped in a paragraph" & @CRLF & _ " because of the blank line preceding it." & @CRLF & _ "" & @CRLF & _ "Term 2" & @CRLF & _ "" & @CRLF & _ ": This definition has a code block, a blockquote and a list." & @CRLF & _ "" & @CRLF & _ " code block." & @CRLF & _ "" & @CRLF & _ " > block quote" & @CRLF & _ " > on two lines." & @CRLF & _ "" & @CRLF & _ " 1. first list item" & @CRLF & _ " 2. second list item" 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