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

/
/
gxJm

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 = "(?xJm)# SETTINGS" & @CRLF & _ " (?<ANCHORED>){1}" & @CRLF & _ " (?<NO_SIGN_DUP>){1}" & @CRLF & _ " (?<PYTHON_POW>){1}" & @CRLF & _ " (?<COMMENTS>){0}" & @CRLF & _ "" & @CRLF & _ "(?(ANCHORED)^(?&s)*)" & @CRLF & _ "(?(DEFINE)" & @CRLF & _ " (?<s>(?(COMMENTS)(?:\s+|\/\*[\s\S]*?\*\/|\/\/.*|\#.*)|\s+))" & @CRLF & _ " (?<sign>(?(NO_SIGN_DUP)(?<=(?<_>[\s\S]))(?!(?P=_)))[-+])" & @CRLF & _ " (?<base>\d+(?:\.\d*)?|\d*\.\d+)" & @CRLF & _ " (?<exp>(?:[eE][+-]?\d+))" & @CRLF & _ " (?<num>(?&sign)?(?&base)(?&exp)?(?!\w))" & @CRLF & _ " (?<bracketed>\((?&s)*(?&expr)(?&s)*\))" & @CRLF & _ " (?<atom>(?&num)|(?&bracketed))" & @CRLF & _ " (?<pow>(?&atom)(?:(?&s)*(?(PYTHON_POW)(?:\^|\*\*)|\^)(?&s)*(?&pow))*)" & @CRLF & _ " (?<mul>(?&pow)(?:(?&s)*[*\/](?&s)*(?&mul))*)" & @CRLF & _ " (?<add>(?&mul)(?:(?&s)*[+-](?&s)*(?&add))*)" & @CRLF & _ " (?<expr>(?&add))" & @CRLF & _ ")" & @CRLF & _ "(?&expr)" & @CRLF & _ "(?(ANCHORED)(?&s)*$)" Local $sString = "0" & @CRLF & _ "::" & @CRLF & _ "1" & @CRLF & _ "::" & @CRLF & _ "+1" & @CRLF & _ "::" & @CRLF & _ "-1" & @CRLF & _ "::" & @CRLF & _ "1.e-1" & @CRLF & _ "::" & @CRLF & _ "1e1" & @CRLF & _ "::" & @CRLF & _ ".1e+1" & @CRLF & _ "::" & @CRLF & _ "-6*((2**(2+4))/3)" & @CRLF & _ "::" & @CRLF & _ "0*0" & @CRLF & _ "::" & @CRLF & _ "0+0" & @CRLF & _ "::" & @CRLF & _ "0/0" & @CRLF & _ "::" & @CRLF & _ "0^0" & @CRLF & _ "::" & @CRLF & _ "0**0" & @CRLF & _ "::" & @CRLF & _ "0-0" & @CRLF & _ "::" & @CRLF & _ "5 - -2" & @CRLF & _ "::" & @CRLF & _ "5- -2" & @CRLF & _ "::" & @CRLF & _ "5+-2" & @CRLF & _ "::" & @CRLF & _ ".1" & @CRLF & _ "::" & @CRLF & _ "1." & @CRLF & _ "::" & @CRLF & _ "1.1" & @CRLF & _ "::" & @CRLF & _ " -2" & @CRLF & _ "::" & @CRLF & _ "5 * (2 + 5 /* comment */ // )" & @CRLF & _ " - 1)" & @CRLF & _ "" & @CRLF & _ "INVALID: // Separated by :: to prevent parsing multiple examples" & @CRLF & _ "." & @CRLF & _ "::" & @CRLF & _ "1e" & @CRLF & _ "::" & @CRLF & _ "1e+" & @CRLF & _ "::" & @CRLF & _ "1e-" & @CRLF & _ "::" & @CRLF & _ "e2" & @CRLF & _ "::" & @CRLF & _ "+" & @CRLF & _ "::" & @CRLF & _ "-" & @CRLF & _ "::" & @CRLF & _ "5 --2" & @CRLF & _ "" & @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