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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'Adapter - BNC Male to BNC-Female, Right Angle Adapter - DB9 Female to DB9-Male, Null Modem Serial Adapter Adapter - RCA Female to RCA-F Adapter - DC Power 2.1x5.5mm Jack to 1.7x4.7mm Plug Adapter - RJ45 Female (8-Pos) to DB25-M Adapter - S-Video to Composite Video Adapter Adapter - N Jack to UHF-M Adapter - BNC Male to BNC-F, Right Angle Adapter - DB9 Female to DB25-M, Serial Comms. Adapter - DB9 Female to DB9-F, Null Modem Serial Adapter Adapter - RCA Female to RCA-F, 10/pkg Adapter - DC Power 2.1x5.5mm Jack to Dual 2.1x5.5mm Plug Adapter - SMA Female to BNC-M Adapter - DB25 Female to DB25-F, Slimline Gender Changer Adapter - DC Power 2.1x5.5mm Plug to 9V Battery Clip, Ctr (+) Adapter - USBA Female to USBA-F, Gender Changer Adapter - USBA Male to USBA-M, Gender Changer Adapter - DB9 Female to DB9-F, Slimline Gender Changer Adapter - BNC Female to N-Type-M Adapter - MCX Male to BNC-F Adapter - DB15 Male to DB15-M, HD Slimline Gender Changer Adapter - DB9 Male to DB9-M, Slimline Gender Changer Adapter - SMA Male to BNC-F'; my $regex = qr/\b-\b/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