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 = 'T203_AL2 T203 T202 PV - slaapkamer 2 T202 CV - slaapkamer 2 1.1 S3-8 - mode 6 1.1 S3-8 - [1] S 1.1 S3-8 - [3] D 1.3 S5-10 - mode !DEFAULT [shift] 1.3 S5-10 - [2] D I/O 0.4 D1_[AUTO : TM s] I/O 0.4 D1_[AUTO : TM l] I/O 0.4 D1_[AUTO] I/O 1.1 S3-8_[6]_LED -2- I/O 1.1 S3-8_[2] -1- #EXTRA INFO REFERENCE for I/O 2.4 S1-4_[4] --- NAME : I/O 2.4 S1-4_[4] -4- --- INFO : K21 [08 I] #EXTRA INFO REFERENCE for 2.4 S5-8 --- NAME : 2.4 S5-8 - mode DEFAULT --- INFO : 2.4 S5-8 [K22] / 4x + LED 2.4 S5-8 [K22] / 4x + LED # HUIS CONTACT HC_1.1_1.2_1.3_1.4 -1- 0.2 cvM1 -1- 1.6 vM2 [speed !MIN/MAX] -1- 1.1 L6/L7/L8 (3 x spots - plafond) -1- 1.B3 L1/L2 (grondspots voordeur) -2- 2.7 V2 SSR1 002 - 0.2 kelder 2 003 - 0.3 kelder 3 [nutsvoorziening] 110 - 1.# SSR B04 - 1.B SSR (all) [F2401] K3 - Q5 : 2.B1 terras slaapkamer [F2308] K3 - Q3 : 2.7 KAST V2 PWR SUPPLY SSR [Nyah-logeer-Caelan] [F1612] K1 - Q1 : 1.9 WC ventilator [10.R1] R501 mode : 1.1 KEUKEN [F1613] K2 - Q1 : 0.2 KELDER CV - [10.R09] R509 + rad lev 0 & 1'; my $regex = qr/(?P<monitor_IO_Elem>^(?P<placeId_IO_Elem>(?:\d{1,2}.\w{1,2}))(?:\ *)(?P<Id_IO_Elem>(?:S|L|P|cvM|vM|V)(?:\d{1,2})(?:\ *)(?:-?)(?:\ *)(?:\d{1,2}))(?:\ )* (?:\-)* (?:\ )*(?:\[)(?P<seqNrPin__IO_Elem>(?:\d){1,2})(?:\])(?:\ *)(?P<action>(?:S|D|T|L|ON|OFF))$)(?:[\n|\r])?/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