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

/
/
gs

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'CBEAM 241678 245002 240528 240628 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241697 245002 240230 240330 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241698 245002 240330 240430 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241699 245002 240430 240530 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241700 245002 240530 240630 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241708 245002 240231 240331 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241709 245002 240331 240431 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241710 245002 240431 240531 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0. CBEAM 241711 245002 240531 240631 10. 0. 10. GOO 0. 0.2750 0. 0. 0.2750 0.'; my $regex = qr/(?<=CBEAM 241699|CBEAM 241711).*?(0\.2750).*?(0\.2750)/sp; 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