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
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

use strict; my $str = 'CALL agr_agreement( 1, 13075, \'HBO Latin America--this is a test\', \'(123) 456-7890\', \'M\', \'John Doe\', \'john@doecom\', \'Miami\', \'(123) 456-7890\', \'Net 30\', \'Quarterly\', 0, \'2014-09-01\', \'2014-09-01\', /* This is a multi\'\'-line comment */ \'2017-08-31\', -- single line comment 36, /*Inline, but multi-line comment*/\'2015-03-26 06:59:44\', @status );'; my $regex = qr/'[^']*(?!\\)'(*SKIP)(*F) # Make sure we're not matching inside of quotes |(?m-s:\s*(?:\-{2}|\#)[^\n]*$) # Single line comment |(?: \/\*.*?\*\/ # Multi-line comment (?(?=(?m-s:[\t ]+$)) # Get trailing whitespace if any exists and only if it's the rest of the line [\t ]+ ) )/xsp; my $subst = ''; 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