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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<div id="feature-bullets" class="a-section a-spacing-medium a-spacing-top-small"> <ul class="a-unordered-list a-vertical a-spacing-none"> <div id="hsx-rpp-bullet-fits-message" class="aok-hidden"> <div class="a-box a-alert-inline a-alert-inline-success hsx-rpp-fitment-bullets"><div class="a-box-inner a-alert-container"><i class="a-icon a-icon-alert"></i><div class="a-alert-content"> This fits your&nbsp;<span class="hsx-rpp-bullet-model-info"></span>. </div></div></div> </div> <li id="replacementPartsFitmentBullet" data-doesntfitmessage="We\'re not sure this item fits your " data-fitsmessage="This fits your " class="aok-hidden"><span class="a-list-item"> <span id="replacementPartsFitmentBulletInner"> <a class="a-link-normal hsx-rpp-fitment-focus" href="#">Make sure this fits</a> <span>by entering your model number.</span> </span> </span></li> <script type="text/javascript"> P.when("ReplacementPartsBulletLoader").execute(function(module){ module.initializeDPX(); }) </script> <li><span class="a-list-item"> Precision ground up-cut spiral design </span></li> <li><span class="a-list-item"> M2 high speed steel runs cooler, lasts longer </span></li> <li><span class="a-list-item"> Includes sizes 1/4" x 3", 1/2" x 3-1/4" and 3/8" x 3" </span></li> <li><span class="a-list-item"> 1/4" shank; </span></li> </ul> <!-- Loading EDP related metadata --> <span class="edp-feature-declaration" data-edp-feature-name="featurebullets" data-edp-asin="B006ZBADNW" data-data-hash="2400652208" data-defects="[{&quot;id&quot;:&quot;defect-mismatch-info&quot;,&quot;value&quot;:&quot;Different from product&quot;},{&quot;id&quot;:&quot;defect-missing-information&quot;,&quot;value&quot;:&quot;Missing information&quot;},{&quot;id&quot;:&quot;defect-unessential-info&quot;,&quot;value&quot;:&quot;Unimportant information&quot;},{&quot;id&quot;:&quot;defect-other-productinfo-issue&quot;,&quot;value&quot;:&quot;Other&quot;}]" data-metadata="CATALOG" data-feature-container-id="" data-custom-event-handler="" data-display-name="Bullet Points" data-edit-data-state="featureBulletsEDPEditData" data-position="" data-resolver="CQResolver"></span> <span class="caretnext">›</span> <a id="seeMoreDetailsLink" class="a-link-normal" href="#productDetails">See more product details</a> </div>'; my $regex = qr/\s*<div\sid=\"feature-bullets[\s\S]*?(<li>\s*[\s\S]*?[\s]+<\/ul>)/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