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

/
/
gxsmJ

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 = "(?xsmJ)(?:(?<=\n)|(?<=\A)) # Necessarily at the begining of a new line or start of string" & @CRLF & _ "(?<leading_space>[ ]{0,3})" & @CRLF & _ "(?<tag_all>" & @CRLF & _ " (?:" & @CRLF & _ " (?<div_open>" & @CRLF & _ " <(?<tag_name>\S+)" & @CRLF & _ " (?<tag_attributes>(?&tag_attr))*" & @CRLF & _ " [^\>]*" & @CRLF & _ " >\n*" & @CRLF & _ " )" & @CRLF & _ " (?<content>.+?)" & @CRLF & _ " \n*" & @CRLF & _ " (?<div_close>" & @CRLF & _ " (?(<leading_space>) # If leading spaces were found" & @CRLF & _ " (?:" & @CRLF & _ " (?<=\n)\g{leading_space} # Either there is a symmetry in leading space for open and closing tag" & @CRLF & _ " |" & @CRLF & _ " (?:(?<=\S)[[:blank:]\h]*) # or the closing tag is on the same line with preceding data" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?=<\/\g{tag_name}>) # No leading space, so we don't expect anything before the closing tag other than what has already been caught in the 'content'" & @CRLF & _ " )" & @CRLF & _ " <\/\g{tag_name}>" & @CRLF & _ " )" & @CRLF & _ " [[:blank:]\h]*\n" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?:" & @CRLF & _ " <!--[[:blank:]\h\v]*(?<html_comment>.*?)[[:blank:]\h\v]*-->" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?:" & @CRLF & _ " <" & @CRLF & _ " [[:blank:]\h\v]*" & @CRLF & _ " (?<tag_name>[a-zA-Z0-9][\w\-]+)" & @CRLF & _ " (?<tag_attributes>(?&tag_attr))*" & @CRLF & _ " [[:blank:]\h\v]*" & @CRLF & _ " \/?" & @CRLF & _ " [[:blank:]\h\v]*" & @CRLF & _ " >" & @CRLF & _ " )" & @CRLF & _ ")" & @CRLF & _ "(?(DEFINE)" & @CRLF & _ " (?<tag_attr>" & @CRLF & _ " (?:" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " [\w\-]+" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " =" & @CRLF & _ " [^\"\'[:blank]\h]+" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?:" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " [\w\-]+" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " =" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " (?<quote>["'])" & @CRLF & _ " (.*?)" & @CRLF & _ " \g{quote}" & @CRLF & _ " [[:blank:]\h]*" & @CRLF & _ " )" & @CRLF & _ " )" & @CRLF & _ ")" Local $sString = "<abbr title="`first backtick!">SB</abbr> " & @CRLF & _ "" & @CRLF & _ "<abbr title="`second backtick!">SB</abbr>" & @CRLF & _ "" & @CRLF & _ "<table>" & @CRLF & _ "<tr><td markdown="block">test _emphasis_ (block)</td></tr>" & @CRLF & _ "</table>" & @CRLF & _ "" & @CRLF & _ "## More complicated" & @CRLF & _ "" & @CRLF & _ "<table>" & @CRLF & _ "<tr><td markdown="1">" & @CRLF & _ "* this is _not_ a list item</td></tr>" & @CRLF & _ "<tr><td markdown="span">" & @CRLF & _ "* this is _not_ a list item</td></tr>" & @CRLF & _ "<tr><td markdown="block">" & @CRLF & _ "* this _is_ a list item" & @CRLF & _ "</td></tr>" & @CRLF & _ "</table>" & @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