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

r"
"
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '0-1:F.F.0*255(000000000000000) 0-1:F.F.2*255(000000000111100) 0-1:0.0.0*255(1ZPA0020280814) 1-0:C.1.0*255(0020280814) 1-0:0.0.2*255(4U110017012) 1-0:0.0.3*255(00000000) 1-0:0.9.1*255(22:38:32) 1-0:0.9.2*255(23-12-28) 1-0:0.2.0*255(05 r01) 1-0:0.1.2*01(231201000000) 1-0:0.1.2*02(231101000000) 1-0:0.1.2*03(231001000000) 1-0:0.1.2&04(230927075308) 1-0:1.8.0*255(000003.6382*kWh) 1-0:1.8.0*254(000003.6382*kWh) 1-0:1.8.0*01(000003.6382*kWh) 1-0:1.8.0*02(000003.6382*kWh) 1-0:1.8.0*03(000003.6382*kWh) 1-0:1.8.0&04(000000.0000*kWh) 1-0:1.8.1*255(000003.6382*kWh) 1-0:1.8.1*254(000003.6382*kWh) 1-0:1.8.1*01(000003.6382*kWh) 1-0:1.8.1*02(000003.6382*kWh) 1-0:1.8.1*03(000003.6382*kWh) 1-0:1.8.1&04(000000.0000*kWh) 1-0:1.8.2*255(000000.0000*kWh) 1-0:1.8.2*254(000000.0000*kWh) 1-0:1.8.2*01(000000.0000*kWh) 1-0:1.8.2*02(000000.0000*kWh) 1-0:1.8.2*03(000000.0000*kWh) 1-0:1.8.2&04(000000.0000*kWh) 1-0:2.8.0*255(000000.6248*kWh) 1-0:2.8.0*254(000000.6248*kWh) 1-0:2.8.0*01(000000.6248*kWh) 1-0:2.8.0*02(000000.6248*kWh) 1-0:2.8.0*03(000000.6248*kWh) 1-0:2.8.0&04(000000.0000*kWh) 1-0:2.8.1*255(000000.6248*kWh) 1-0:2.8.1*254(000000.6248*kWh) 1-0:2.8.1*01(000000.6248*kWh) 1-0:2.8.1*02(000000.6248*kWh) 1-0:2.8.1*03(000000.6248*kWh) 1-0:2.8.1&04(000000.0000*kWh) 1-0:2.8.2*255(000000.0000*kWh) 1-0:2.8.2*254(000000.0000*kWh) 1-0:2.8.2*01(000000.0000*kWh) 1-0:2.8.2*02(000000.0000*kWh) 1-0:2.8.2*03(000000.0000*kWh) 1-0:2.8.2&04(000000.0000*kWh) 1-0:0.2.2*255(00750101) 1-0:C.15.0*255(23-04-07) 1-0:0.2.6*255(intErn) 1-0:C.6.0*255(00 00:07:33) 1-0:C.14.0*255(T2) 1-0:C.9.0*255(+27.0*C) 1-0:C.6.3*255(3.66*V) 1-0:C.1.6*255(98FC51FF)'; my $regex = qr/^((?P<a>[0-9]{1,3})-)?((?P<b>[0-9]{1,3}):)?(?P<cde>(?P<c>[0-9A-F]{1,3}).(?P<d>[0-9A-F]{1,3})(.(?P<e>[0-9A-F]{1,3}))?)([\*\&](?P<f>[0-9A-F]{1,3}))?\((?P<value>[^*^\)]*)(([\*])(?P<unit>\w*))?\)$/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