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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'https://medium.com/@s.vive00/7-changes-i-experienced-after-going-1-week-without-added-sugar-9bc48b667f87?source=email-8f87fbd013ca-1581664260785-digest.weekly------0-58------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top https://medium.com/@DrAyala/exercise-is-the-answer-heres-why-it-s-a-weight-loss-underperformer-8b64103b8c8f?source=email-8f87fbd013ca-1581664260785-digest.weekly------1-59------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top#Fragment-identifier https://www.medium.com/@DrAyala/exercise-is-the-answer-heres-why-it-s-a-weight-loss-underperformer-8b64103b8c8f?source=email-8f87fbd013ca-1581664260785-digest.weekly------1-59------------------2882ae9f_a61e_4d5c_9f87_24f3e0d54cc9-1-----&sectionName=top#Fragment-identifier http://www.yoursite.com/path/to/file.mp3 http://example.com/data.csv#row=4 http://example.com/bar.webm#t=40,80&xywh=160,120,320,240 example.com/data.csv#row=4 example.co.uk/data.csv#row=4'; my $regex = qr/^(?<Scheme>[file|ftp|https{0,1}|ldap|telnet]+:\/{2})?(?<Subdomain>[a-zA-Z0-9-]{0,4}\.)?(?<Domain>\w+\.\w+\.?\w+\/)(?<Subdirectory>@[\w.]+\/)?(?<Path>[\w_~.-]+\/?[\w_-]+\/{0,1}?[\w_~.-]+)(?<Query>[%?&;].[\w&_~.=-]+)?(?<Fragment>#?[\/\w_-~.,=&-]+)?$/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