Regular Expressions 101

Save & Manage Regex

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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 = ' [openandclose src="1234" id="abc"]some content[/openandclose] [openwithattrs src="1234" id="abc"] [mmbox_with-attrs title="TOOL: Track Your Net Worth - Personal Capital" link="https://go.millennialmoney.com/personal-capital/" image="https://millennialmoney.com/wp-content/uploads/2020/05/personal-capital-square.jpg" ctatext="Get Started!" desc="With Personal Capital, you can see your net worth, analyze investments, and discover any hidden fees you weren&#8217;t aware of before &#8211; as well as set spending and saving goals." price="FREE" color="#32C4F3"] [HL_QUOTER] [open_only-] [mmtoplist_ma type="Auto" max="2" header="0"] [tmf_investnow500 source="isammtxt0000006" header="Where to invest $1000 right now" aside="Even More Stock Picks" link="https://www.fool.com/order/fe_offers/wf/602d8976-8f2f-41c3-9ddf-1ab6c2b5ba06?c=sa-inv-btr&amp;amp;utm_campaign=topmillennialtrends&amp;amp;utm_medium=ecap_widget&amp;amp;utm_source=millennialmoney&amp;amp;campaign=sa-bbn-evergreen"] [earningPotential amount="$50,371" timeframe="yr"] [earningPotential]'; my $regex = qr/\[(\[?)(?P<shortcodename>\w\S+)(?![/w-])([^\]\/]*(?:\/(?!\])[^\]\/]*)*?)(?:(\/)\]|\](?:([^\[]*(?:\[(?!\/\2\])[^\[]*)*)\[\/\2\])?)(\[?)/p; 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