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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'WDL3-4N-C4510-1A#show inventory NAME: "Switch System", DESCR: "Cisco Systems, Inc. WS-C4510R+E 10 slot switch " PID: WS-C4510R+E , VID: V03 , SN: FOX1616GNS8 NAME: "Clock Module", DESCR: "Clock Module" PID: WS-X4K-CLOCK-E , VID: V01 , SN: NWG161794PT NAME: "Mux Buffer 1 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179CP9 NAME: "Mux Buffer 2 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179C3T NAME: "Mux Buffer 3 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179CUN NAME: "Mux Buffer 4 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179AXZ NAME: "Mux Buffer 7 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179CTE NAME: "Mux Buffer 8 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179C3V NAME: "Mux Buffer 9 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179CLW NAME: "Mux Buffer 10 ", DESCR: "Mux Buffers for Redundancy Logic" PID: WS-X4590-EX= , VID: , SN: NWG16179CVU NAME: "Linecard(slot 1)", DESCR: "10/100/1000BaseT (RJ45)+V E Series with 48 10/100/1000 baseT Premium PoE ports (Cisco/IEEE)" PID: WS-X4748-RJ45V+E , VID: V03 , SN: CAT1624L2J7 '; my $regex = qr/(NAME)((\s)?:(\s)?)([ |,| (|)|\\|\.|\"|\w|\-|\+]*)((\s)*?,(\s)*?)(DESCR)((\s)?:(\s)?)([ |,| (|)|\\|\.|\"|\w|\-|\+]*)(\s)(PID)((\s)?:(\s)?)([\w|\-|\+|=]+)((\s)+,(\s)+)(VID)((\s)?:(\s)?)([\w| ]*)((\s)+,(\s)+)(SN)((\s)?:(\s)?)([\w| ]*)/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