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 = ' 1 UA 990J 28OCT SFOCDG 340P 1015A 29OCT greg 2 AF1830J 31OCT CDGMXP 900A 1025A 31OCT OPERATED BY AIR CANADA YYZ CHECK-IN WITH AIR CANADA 3 LH 259J 03NOV T MXPFRA 740A 900A 03NOV OPERATED BY LUFTHANSA MAD CHECK-IN WITH LUFTHANSA 4 DL2252Z 01OCT T SATDTW*SS1 1246P 454P 5 DL 98Z 01OCT T DTWCDG*SS1 608P 805A 02OCT W /DCDL /E 6 DL8322Z 02OCT W CDGBOD*SS1 935A 1050A /DCDL /E OPERATED BY AIR FRANCE grggf rge 7 DL9365Z 09OCT W BODAMS*SS1 1150A 140P /DCDL /E OPERATED BY KLM ROYAL DUTCH AIRLINES 8 DL8178Z 09OCT W AMSSLC*SS1 500P 655P /DCDL /E OPERATED BY KLM ROYAL DUTCH AIRLINES fre f 10 LH 454J 03NOV FRASFO 1005A 205P 03NOV 11 LH 454J 03NOV SFOKIV 205P 235P 03NOV'; my $regex = qr/(\d+)\s+(\w{2})\s*(\w{2,5})\s+(\w{5})(?:\s+|\s+(.)\s+)(\w{3})(\w{3})(?:\s+|(?:\s|\*)(\w{3})\s+)(\w{4,5})\s+(\w{4,5})(?:\s+(\w{5}))?.*(?:\n|$)??((?:.|\n)*?)(\n\s*\n)?(?=\d+\s+\w{2}\s*\w{2,5}\s+\w{5}(?:\s+|\s+.\s+)\w{3}\w{3}(?:\s+|(?:\s|\*)\w{3}\s+)\w{4,5}\s+\w{4,5}(?:\s+\w{5})?|$)/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