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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = '## comment # #comment ! Basic rules ##div #@#div ##.ads #@#.ads ###ads #@##ads example.com,~example.org##div example.com,~example.org#@#div example.com,~example.org##.ads example.com,~example.org#@#.ads example.com,~example.org###ads example.com,~example.org#@##ads ! HTML filtering rules ! https://github.com/gorhill/uBlock/wiki/Static-filter-syntax#html-filters example.com##^.badstuff example.com##^script:has-text(7c9e3a5d51cdacfc) ! https://adguard.com/kb/general/ad-filtering/create-own-filters/#html-filtering-rules example.org$$script[data-src="banner"] example.org$@$script[data-src="banner"] ! CSS rules ! https://adguard.com/kb/general/ad-filtering/create-own-filters/#cosmetic-css-rules example.com#$#div { visibility: hidden; } example.com#@$#div { visibility: hidden; } example.com#$#.textad { visibility: hidden; } example.com#@$#.textad { visibility: hidden; } example.com#$##textad { visibility: hidden; } example.com#@$##textad { visibility: hidden; } ! Extended CSS selectors ! https://adguard.com/kb/general/ad-filtering/create-own-filters/#extended-css-selectors example.com#?#div:has(> a[target="_blank"][rel="nofollow"]) example.com#@?#div:has(> a[target="_blank"][rel="nofollow"]) example.com#?#.banner:matches-css(width: 360px) example.com#@?#.banner:matches-css(width: 360px) example.com#?##banner:matches-css(width: 360px) example.com#@?##banner:matches-css(width: 360px) example.com#$?#div:has(> span) { display: none !important; } example.com#@$?#div:has(> span) { display: none !important; } example.com#$?#.banner:has(> span) { display: none !important; } example.com#@$?#.banner:has(> span) { display: none !important; } example.com#$?##banner:has(> span) { display: none !important; } example.com#@$?##banner:has(> span) { display: none !important; } ! JavaScript rules ! https://adguard.com/kb/general/ad-filtering/create-own-filters/#javascript-rules ! https://adguard.com/kb/general/ad-filtering/create-own-filters/#scriptlets example.com#%#window.__gaq = undefined; example.com#@%#window.__gaq = undefined; ! Scriptlet rules example.com##+js(aopw, Fingerprint2) example.com#@#+js(aopw, Fingerprint2) example.org,example.com#%#//scriptlet("abort-on-property-read", "alert") example.com#@%#//scriptlet("abort-on-property-read")'; my $regex = qr/^(?!##?\s)([^\/\|\@\"!]*?)(##|#[@?$%]{1,3}#|\$@?\$)/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html