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

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = 'Frank Kreienkamp1, Sjoukje Y. Philip2, Jordis S. Tradowsky1,4, Sarah F. Kew2, Philip Lorenz1, Julie Arrighi7,8,9, Alexandre Belleflamme16, Thomas Bettmann18, Steven Caluwaerts13,19, Steven C. Chan14, Andrew Ciavarella22, Lesley De Cruz13, Hylke de Vries2, Norbert Demuth18, Andrew Ferrone17, Erich M. Fischer6, Hayley J. Fowler14, Klaus Goergen16, Dorothy Heinrich7, Yvonne Henrichs18, Geert Lenderink2, Frank Kaspar10, Enno Nilson15, Friederike E L Otto11, Francesco Ragone13,20, Sonia I. Seneviratne6, Roop K. Singh7, Amalie Skålevåg1, Piet Termonia13,19, Lisa Thalheimer11, Maarten van Aalst7,8,21, Joris Van den ergh13, Hans Van de Vyver13, Stéphane Vannitsem13, Geert Jan van Oldenborgh2,3, Bert Van Schaeybroeck13, Robert Vautard5, Demi Vonk8, Niko Wanders'; my $regex = qr/((?P<fname>[A-Za-zåé]+ ?[A-Za-zåé]+\.? ?)+ (?P<lname>[A-Za-zåé]+\.? ?))(?:(?:\d+,)+ ?)?/mp; my $subst = '\\g<1>\\n'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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