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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"
"
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)\[(?:http://|https://)*(?:\w+\.)*(\w+(?:\.(?:com|org|net|edu|gov|info|biz|io|co|app|co|uk|de|jp|ca|dev|app|gg))+)]\((?:http://|https://)(?:\w+\.)+\w+(?:/\w+)*\)" Local $sString = "Normal links don't get caught:" & @CRLF & _ "[do not catch this](https://example.com)" & @CRLF & _ "orthis.com" & @CRLF & _ "" & @CRLF & _ "Neither do links with full stops in the message:" & @CRLF & _ "(messages. with. full stops)[https://example.com]" & @CRLF & _ "" & @CRLF & _ "even if they forget a space" & @CRLF & _ "[whoops.nospace](https://example.com)" & @CRLF & _ "" & @CRLF & _ "because we catch based on tld:" & @CRLF & _ "[catchthis.com](https://malicious.link)" & @CRLF & _ "[catchthis.org](https://malicious.link)" & @CRLF & _ "[catchthis.net](https://malicious.link)" & @CRLF & _ "[catchthis.edu](https://malicious.link)" & @CRLF & _ "[catchthis.gov](https://malicious.link)" & @CRLF & _ "[catchthis.info](https://malicious.link)" & @CRLF & _ "[catchthis.biz](https://malicious.link)" & @CRLF & _ "[catchthis.io](https://malicious.link)" & @CRLF & _ "[catchthis.co](https://malicious.link)" & @CRLF & _ "[catchthis.uk](https://malicious.link)" & @CRLF & _ "[catchthis.de](https://malicious.link)" & @CRLF & _ "[catchthis.jp](https://malicious.link)" & @CRLF & _ "" & @CRLF & _ "[www.catchthis.com](https://malicious.link)" & @CRLF & _ "[https://catchthis.com](https://malicious.link)" & @CRLF & _ "[http://catchthis.com](http://malicious.link)" & @CRLF & _ "" & @CRLF & _ "any combination of the above also gets matched for multiple tld urls:" & @CRLF & _ "[link.co.jp.org.net](https://malicious.link)" & @CRLF & _ "" & @CRLF & _ "This is perfect because we can block any malicious link with any tld or any number of subdomains, but have a controlled list of tlds that links with a fake url begin with. Since most non-standard tlds are sketchy, we don't even need that many:" & @CRLF & _ "" & @CRLF & _ "[link.com](http://any.malicious.li.nk/anything/at/all)" & @CRLF & _ "" & @CRLF & _ "Any number of subdomains also get caught:" & @CRLF & _ "[auth.google.com](https://malicious.website.com)" & @CRLF & _ "[any.number.at.all.com](https://malicious.link)" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "This method of having a set tld list means almost zero false positives, with the drawback of people having to recognise sketchy urls themselves:" & @CRLF & _ "" & @CRLF & _ "[linkwitha.sketchytld](https://malicious.link) // not caught" & @CRLF & _ "" & @CRLF & _ "If you want a wider net with a higher chance of false positives, replace the subdomains with the word matcher wildcard (\w+):" & @CRLF & _ "" & @CRLF & _ "\[(?:\w+\.)*(\w+(?:\.(?:\w+))+)]\((?:http://|https://)(?:\w+\.)+\w+(?:/\w+)*\)" & @CRLF & _ "" & @CRLF & _ "Or a much shorter one that doesn't catch http:// links but that is short enough for Discord: [discord already blocks "fake" links with https in the title but not ones without it]" & @CRLF & _ "" & @CRLF & _ "\[(\w+\.?)*]\((https?://)(\w+\.?)*\)" & @CRLF & _ "" & @CRLF & _ "a longer method with subdomain denylisting is also short enough for Discord:" & @CRLF & _ "" & @CRLF & _ "\[(?:(?:www|auth|login)\.)*(\w+(?:\.(?:com|org|net|edu|gov|info|biz|io|co|app|co|uk|de|jp|ca|dev|app|gg))+)]\((?:http://|https://)(?:\w+\.)+\w+(?:/\w+)*\)" & @CRLF & _ "" & @CRLF & _ "Since this compiles to a shorter resulting regex (add more subdomains after auth to catch more. )" 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