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
Processing...

Test String

Substitution
Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?m)(?<=\s)((?:docstring|some_detailed_notes)\s*=\s*\(?\s*(?://.*\n\s*)*)"((?:[^"\\]|\\.)+)"(\s*\)?\s*;)" Local $sString = "class myClassA(myBaseClass) {" & @CRLF & _ "" & @CRLF & _ " docstring = // End-of-line-comments possible" & @CRLF & _ """ & @CRLF & _ "This is my class description docstring stored in a string variable inherited from" & @CRLF & _ "myBaseClass." & @CRLF & _ "The content of this string, INCLUDING INDENTATION, MUST NOT be changed." & @CRLF & _ "";" & @CRLF & _ "" & @CRLF & _ "docstring = (" & @CRLF & _ """ & @CRLF & _ "Enclosed in parentheses" & @CRLF & _ """ & @CRLF & _ ");" & @CRLF & _ "" & @CRLF & _ " // This variable is declared as string has a mismatched indentation:" & @CRLF & _ "string some_detailed_notes = "Some string like this is also possible." & @CRLF & _ " Also with" & @CRLF & _ " some really" & @CRLF & _ " strange indentation" & @CRLF & _ " and `inline code`, ```code blocks``` $\\text{LaTeX}$ $$\\frac{1}{2}$$" & @CRLF & _ ":::{hint}" & @CRLF & _ "some admonitions" & @CRLF & _ ":::" & @CRLF & _ "and all kind of special characters such as:" & @CRLF & _ "\"" & @CRLF & _ "(...)" & @CRLF & _ "{...}" & @CRLF & _ "[...]" & @CRLF & _ ";.," & @CRLF & _ "etc." & @CRLF & _ "" & @CRLF & _ "which MUST be preserved.";" & @CRLF & _ "" & @CRLF & _ " string some_other_string = "" & @CRLF & _ " do NOT touch this, only docstring and some_detailed_notes" & @CRLF & _ " ";" & @CRLF & _ "}" Local $sSubst = "\1R""""\2""""\3" Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst) MsgBox($MB_SYSTEMMODAL, "Result", $sResult)

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