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
No Match

/
/
gmi

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<br data-a1="nope" attr=" jepp@get.me " data-a2="nope"> <br data-a1="nope" attr=\' jepp@get.me \' data-a2="nope"> <br data-a1="nope" attr=jepp@get.me data-a2="nope"> <br data-a1="nope" attr=" jepp@get.me " data-a2="nope"/> <br data-a1="nope" attr=" jepp@get.me " data-a2="nope" /> <tag data-a1="nope" attr=" jepp@get.me " data-a2="nope">text</tag> <tag data-a1="nope" attr=\' jepp@get.me \' data-a2="nope">text</tag> <tag data-a1="nope" attr=jepp@get.me data-a2="nope">text</tag> <tag data-a1="nope" attr=" additional text jepp@get.me \'additional text\'" data-a2="nope">text</tag> <tag data-a1="nope" attr=" additional text jepp@get.me additional text" data-a2="nope">text</tag> <tag data-a1="nope" attr=\' additional text jepp@get.me "additional text"\' data-a2="nope">text</tag> <tag data-a1="nope" attr=" jepp@get.me jeppagain@get.me " data-a2="nope">text</tag> abc dont@get.me 123 <input value="please@get.me">xyz abc dont@get.me 123 <tag1 att1="val1" email1="please@get.me">xyz abc dont@get.me 123 <tag2 att1="val1" email2="please@get.me" att1="val1">xyz <tag2 att1="val1" email3=\'please@get.me\' att1="val1">xyz <tag2 att1="val1" email4=please@get.me att1="val1">xyz <tag2 att1="val1" email5=" please@get.me " att1="val1">xyz <tag2 att1="val1" email6=\' please@get.me \' att1="val1">xyz <tag data-yeah-also-valid-attr-name="please@get.me">xyz <tag data-yeah-attr="please@get.me"> <tag data-yeah-attr=\'please@get.me\'> <tag data-yeah-attr=please@get.me> <tag data-yeah-attr="\'please@get.me\'"> <tag data-yeah-attr=\'"please@get.me"\'>'; my $regex = qr/<\w+.*?([\w-]+=["']*\s*(?:\w+\s*)*[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\s*(?:['"]?(?:\w+\s*)*['"]?)?["']*).*?>/mip; 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