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

Substitution

Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?m)(?:(^(?:\s*)\/{4,}\n)+(^(\s*)\/{2,3}(?!\/)[\s\S]*\n)*\1)" Local $sString = "namespace sf {" & @CRLF & _ "////////////////////////////////////////////////////////////" & @CRLF & _ "/// \ingroup system" & @CRLF & _ "/// \brief Return a pointer to the Android native activity" & @CRLF & _ "/// " & @CRLF & _ "/// You shouldn't have to use this function, unless you want" & @CRLF & _ "/// to implement very specific details, that SFML doesn't" & @CRLF & _ "/// support, or to use a workaround for a known issue." & @CRLF & _ "///" & @CRLF & _ "/// \return Pointer to Android native activity structure" & @CRLF & _ "///" & @CRLF & _ "/// \sfplatform{Android,SFML/System/NativeActivity.hpp}" & @CRLF & _ "///" & @CRLF & _ "////////////////////////////////////////////////////////////" & @CRLF & _ "SFML_SYSTEM_API ANativeActivity* getNativeActivity();" & @CRLF & _ "" & @CRLF & _ " ////////////////////////////////////////////////////////////" & @CRLF & _ " // a " & @CRLF & _ " ////////////////////////////////////////////////////////////" & @CRLF & _ "" & @CRLF & _ "} // namespace sf" Local $sSubst = "$3/**\n$2$3 */\n" 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