Regular Expressions 101

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  • Unit Tests (18)

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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
No Match

r"
"
gmix

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 $sRegex = "(?mix)(?:" & @CRLF & _ " (?<!\S)@ # Match "@" only if it's not preceded by a non-whitespace character" & @CRLF & _ " | # OR" & @CRLF & _ " (?:" & @CRLF & _ " # Telegram link types reference: https://core.telegram.org/api/links" & @CRLF & _ " #" & @CRLF & _ " (?:https?://)? # Optional HTTP or HTTPS protocol" & @CRLF & _ " (?:www\.)? # www subdomain" & @CRLF & _ " (?:t\.me|telegram\.(?:me|dog)) # Match "t.me", "telegram.me", or "telegram.dog" domains" & @CRLF & _ " / # Ensure a forward slash after the domain" & @CRLF & _ " | # OR" & @CRLF & _ " tg://resolve\?domain= # Match Telegram deep link schema (tg://resolve?domain=)" & @CRLF & _ " )" & @CRLF & _ " | # OR" & @CRLF & _ " (?=\b # Positive lookahead: Ensure a valid subdomain before username" & @CRLF & _ " (?!\w*__) # Disallow double underscores anywhere in the username" & @CRLF & _ " (?!\w*_{2,}) # Disallow underscores at the start or end of username" & @CRLF & _ " (?:[a-z][a-z0-9_]{3,31}) # Username" & @CRLF & _ " (?<!_) # Disallow usernames ending with an underscore" & @CRLF & _ " \.t\.me$ # Ensure it ends with ".t.me"" & @CRLF & _ " )" & @CRLF & _ ")" & @CRLF & _ "(?P<username> # Start capturing the username" & @CRLF & _ " (?!\w*_{2,}) # Disallow double underscores in the username" & @CRLF & _ " (?!\w*[^0-9a-z_.,\s]) # Ensure valid characters (letters, numbers, underscores, dots, commas, spaces)" & @CRLF & _ " (?:[a-z][a-z0-9_]{3,31}) # Username" & @CRLF & _ " (?<!_) # Disallow username ending with an underscore" & @CRLF & _ " \b # Ensure it's a valid word boundary" & @CRLF & _ ")" & @CRLF & _ "(?:\.t\.me)? # Optional ".t.me" subdomain" Local $sString = "@username" & @CRLF & _ "@user_name" & @CRLF & _ "@username123" & @CRLF & _ "@alanbadoev @orkester okinea.t.me" & @CRLF & _ "@username123_, @username123" & @CRLF & _ "@username123, @username123_" & @CRLF & _ "@username123, username123.t.me" & @CRLF & _ "@name_with_underscore" & @CRLF & _ "@user$name" & @CRLF & _ "@user__name" & @CRLF & _ "@username_" & @CRLF & _ "@user name" & @CRLF & _ "@toolongusernameeeeeeeeeeeeeeeeeee" & @CRLF & _ "@123username" & @CRLF & _ "https://t.me/username" & @CRLF & _ "https://www.t.me/username" & @CRLF & _ "http://t.me/username" & @CRLF & _ "t.me/username" & @CRLF & _ "tg://resolve?domain=username" & @CRLF & _ "username.t.me" & @CRLF & _ " username.t.me" & @CRLF & _ "https://t.me/@username" & @CRLF & _ "http://t.me/user__name" & @CRLF & _ "username_.t.me" & @CRLF & _ "user__name.t.me" & @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