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

/
/
gu

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 = "(?u)#\{(?![.\d])(?=(?<inner>(?:[\-_]{0,4}(?<![\-_]{5})[\p{L}\d]{2,}[\.\-_]?[\-_]{0,3})+))\1(?<!\.)\}" Local $sString = "- Must start with `#{`, not captured. " & @CRLF & _ "- Must end with `}`, not captured." & @CRLF & _ "- Named capture group 'inner' within the brackets." & @CRLF & _ "- Must only contain periods, dashes, underscores, unicode letters, and 0-9 digits." & @CRLF & _ "- Must contain at least two unicode letters, or at least one unicode letter and digit." & @CRLF & _ "- Cannot begin or end with a period. Ex.`#{.foo.}`not matched." & @CRLF & _ "- Cannot start with a digit. Ex. `#{42_digitAtStart}` is not matched." & @CRLF & _ "- No periods before unicode chars, Ex. `#{_.foo}` is not matched." & @CRLF & _ "- Two periods cannot be next to one another. Ex. `#{foo.bar}` is OK, but `#{foo..bar}`, `#{.foo}`, and `#{foo.}` are not." & @CRLF & _ "- cannot contain any mix of more than 4 dashes or underscores next to one another. Eg. `#{foo____}` and `#{-_-_foo-bar_-_-}` are OK, but `#{--___ foo}` and `#{bar-_-_--} are not." & @CRLF & _ "" & @CRLF & _ "MUST MATCH" & @CRLF & _ "#{alpha} #{beta} #{charlie}" & @CRLF & _ "#{ìñtérnâtiônàlizàtïon}" & @CRLF & _ "#{مرحبا} #{こんにちは} #{мир}" & @CRLF & _ "#{-dashes-}" & @CRLF & _ "#{_under_scores_}" & @CRLF & _ "#{dots.and-dashes-and_under_scores}" & @CRLF & _ "#{some_ASCII_Digits_12345}" & @CRLF & _ "#{a2ndPositionDigit}" & @CRLF & _ "#{test.foo.bar.baz}" & @CRLF & _ "#{outer_must_not_match#{#{only_deepest_must_match}}}" & @CRLF & _ "#{____fourUnderscoresAndDashesTogether}" & @CRLF & _ "#{fourDashes-_--}" & @CRLF & _ "#{a2} // One letter and one digit" & @CRLF & _ "#{period._} // Note period BEFORE letters is not allowed" & @CRLF & _ "" & @CRLF & _ "MUST NOT MATCH" & @CRLF & _ "#{} // Empty" & @CRLF & _ "#{a} #{-} #{_} // Single characters" & @CRLF & _ "#{42_digitAtStart}" & @CRLF & _ "#{0123456789} // Only digits" & @CRLF & _ "#{.periodAtStart}" & @CRLF & _ "#{periodAtEnd.}" & @CRLF & _ "#{moreThanOnePeriod..Together}" & @CRLF & _ "#{a.singleStartingCharacterFollowedByPeriod}" & @CRLF & _ "#{#non-Dash_Underscore_Period.Symbols}" & @CRLF & _ "#{---} // Only Dashes" & @CRLF & _ "#{-_-} // Only dashes and underscores" & @CRLF & _ "#{_-_}" & @CRLF & _ "#{-_-_-moreThanFourModifiers}" & @CRLF & _ "#{_.dotBeforeCharacters}" & @CRLF & _ "#{-_-_-moreThanFourModifiers}" & @CRLF & _ "#{modifiers-----five}" & @CRLF & _ "#{modifiers______six}" & @CRLF & _ "#{modifiers-------seven}" & @CRLF & _ "#{modifiers_-_-_-_-eight}" & @CRLF & _ "#{moreThanFourModifiers-_-_-}" & @CRLF & _ "#{last\} // escape backslashes" & @CRLF & _ "#{\first}" & @CRLF & _ "#{mid\dle}" 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