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]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<td valign="top"><br> <br> John Doe<br> Example, Inc. <br> <br> Office: 212.777.9999 x295<br> jdoe@example.com| transbeam.com <br> <br> Support Escalations<br> Level I: NOC Technician - support@example.com | O: 989.571.1000<br> Level II: Manager, Network &amp; Eng Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br> Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br> Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br> <br> <br> <br> From: Example Tech Support <br> Sent: Monday, August 7, 2017 3:27 PM<br> To: Example Tech Support <support@example.com>; \'nocdata@sample.com\' <nocdata@sample.com><br> Subject: RE: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br> <br> Sample Support,<br> <br> Please be advised all loops have been repaired for this customer and they are currently up at their Full Bandiwdth.<br> As this is stable, We will close this ticket out.<br> <br> Please let us know if you have any questions.<br> <br> Thank you,<br> <br> John Doe<br> Example, Inc. <br> <br> Office: 212.777.9999 x295<br> jdoe@example.com| transbeam.com <br> <br> Support Escalations<br> Level I: NOC Technician - support@example.com | O: 989.571.1000<br> Level II: Manager, Network &amp; Eng Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br> Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br> Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br> <br> <br> <br> From: Example Tech Support <br> Sent: Thursday, August 3, 2017 9:24 AM<br> To: Example Tech Support <support@example.com>; \'nocdata@sample.com\' <nocdata@sample.com><br> Subject: RE: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br> <br> Correction. The commit on the new ticket (loop 4) is 08/16. Apologies for the error.<br> <br> -------------------------------------<br> Judy Garland<br> NOC Technician<br> <br> From: Example Tech Support <br> Sent: Thursday, August 03, 2017 9:22 AM<br> To: \'nocdata@sample.com\'<br> Cc: Example Tech Support<br> Subject: 81434 | WIN - Reparian Riverfront - EoC 10MB - Partial Impact<br> <br> Hello,<br> <br> Update regarding results of ILEC dispatch to prem this date. ILEC technician repaired the loop that was down (loop 3), but another loop (loop 4) developed a problem while he was there and is now bouncing. Loop 4 has been removed from the efm-group to prevent it from affecting the circuit and a ticket opened with the ILEC for its repair (commit 08/14).<br> <br> At this time, the 10Mb circuit is up at 9.8Mbps on 3 loops.<br> <br> <br> If you have any further questions, comments or concerns regarding this message, please contact Example NOC support as documented below.<br> <br> Thank you,<br> <br> -------------------------------------<br> Judy Garland<br> NOC Technician<br> <br> transbeam.com<br> <br> =======================================================================<br> Support Escalations<br> Level I: NOC Technician - support@example.com | O: 989.571.1000<br> Level II: Manager, Network Operations, William Tell - wchen@example.com | O: 212.777.9999 x123 | M: 989.265.9876<br> Level III: Vice President, Operations, Blaise Pascal - blaisep@example.com | O: 212.777.9999 x234 | M: 343.301.2822 <br> Level IV: Chief Operating Officer: BF Skinner - bskinner@example.com | O: 212.777.9999 x345 | M: 343.337.7775<br> <br> </td>'; my $regex = qr/Support Escalations*[\s\S]*?Level IV.*/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