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

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)^ *[^\s]+( +[^\s]+)*$" Local $sString = "# UFIS : User-Friendly and Instant Installer System" & @CRLF & _ "" & @CRLF & _ "# Each comment starts with '#' and ends with a new line." & @CRLF & _ "# Each statement is written in one line." & @CRLF & _ "# Commands' and built-in variables' names are always uppercase." & @CRLF & _ "# A custom variable name must have at least one lowercase character and must begin with a letter or the underscore (_)." & @CRLF & _ "" & @CRLF & _ "LET APP_NAME = "MyApp"" & @CRLF & _ "LET APP_VERSION = "1.0.0"" & @CRLF & _ "" & @CRLF & _ "LET a = MATERIAL "folderx/"" & @CRLF & _ "a -= "test.exe"" & @CRLF & _ "a -= "main.exe"" & @CRLF & _ "a += MATERIAL "folderz/"" & @CRLF & _ "a += MATERIAL "README.md"" & @CRLF & _ "" & @CRLF & _ "LET b = MATERIAL "folderx/test.exe"" & @CRLF & _ "" & @CRLF & _ "LET c = MATERIAL "folderx/main.exe"" & @CRLF & _ "" & @CRLF & _ "IF INSTALLING" & @CRLF & _ " LET iAcceptLicense = INPUT CHECKBOX "Accept [license](https://myapp.com/license)" MANDATORY" & @CRLF & _ " IF iAcceptLicense == FALSE" & @CRLF & _ " QUIT" & @CRLF & _ " ENDIF" & @CRLF & _ "" & @CRLF & _ " LET iLanguage = INPUT CHOICES "Vietnamese" OR "English" DEFAULT "English" MANDATORY" & @CRLF & _ "" & @CRLF & _ " LET INSTALL_DIR = INPUT DIRECTORY "Installation directory" POSTFIX "/${APP_NAME}" DEFAULT PROGRAM_FILES" & @CRLF & _ " LET iInstallTest = INPUT CHECKBOX "Install test.exe" DEFAULT FALSE" & @CRLF & _ " LET iCreateDesktopShortcut = INPUT CHECKBOX "Create desktop shortcut" DEFAULT TRUE" & @CRLF & _ " LET iLaunchAtStartup = INPUT CHECKBOX "Launch program at startup" DEFAULT TRUE" & @CRLF & _ "" & @CRLF & _ " INSTALL a AND c TO INSTALL_DIR # the same as "${INSTALL_DIR}"" & @CRLF & _ "" & @CRLF & _ " IF iInstallTest == TRUE" & @CRLF & _ " INSTALL b TO INSTALL_DIR AS "test_program.exe"" & @CRLF & _ " ENDIF" & @CRLF & _ "" & @CRLF & _ " IF iCreateDesktopShortcut == TRUE" & @CRLF & _ " CREATE SHORTCUT FOR c IN DESKTOP_ALL_USERS" & @CRLF & _ " ENDIF" & @CRLF & _ "" & @CRLF & _ " IF iLaunchAtStartup == TRUE" & @CRLF & _ " RUN c AT STARTUP" & @CRLF & _ " ENDIF" & @CRLF & _ " " & @CRLF & _ " WORK registry_work" & @CRLF & _ " CREATE REGSZ "HKEY_LOCAL_MACHINE/Software/${APP_NAME}" VALUE "1"" & @CRLF & _ " ENDWORK" & @CRLF & _ " " & @CRLF & _ " CPP" & @CRLF & _ " #include <iostream>" & @CRLF & _ " " & @CRLF & _ " void entry() {" & @CRLF & _ " std::cout << "Not very intelligent";" & @CRLF & _ " }" & @CRLF & _ " ENDCPP" & @CRLF & _ " " & @CRLF & _ " CALL entry" & @CRLF & _ "" & @CRLF & _ "ELIF RUNNING" & @CRLF & _ " RUN c" & @CRLF & _ "" & @CRLF & _ "ELSE # UNINSTALLING" & @CRLF & _ " UNDO ALL EXCEPT registry_work" & @CRLF & _ "" & @CRLF & _ "ENDIF" & @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