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 = 'First Name Melissa Last Name Madrid Phone 4253068210 E-Mail Meli.madrid@yahoo.com What is your age group? 19-39 Without my glasses and contacts-Farsightedness : I have trouble reading and seeing things up close yes Without my glasses and contacts-Astigmatism : I have distorted vision and cannot see very well yes What do you usually wear?-Glasses yes What do you usually wear?-Contacts yes What do you usually wear?-Reading Glasses yes Do you have any of the following?-None of the above yes I would like to see well at a distance without relying on glasses and contact lenses. 5 I would like to see well up close without relying on glasses and contact lenses. 5 Would your career or business activities improve if you were to become less dependent on glasses and contacts? Yes Test Score -4.00 The message has been sent from 107.77.205.32 (United States) at 2020-01-10 10:39:44 on iPhone unknown Entry ID: 2190 Referrer: http://m.facebook.com Form Host: https://www.nweyes.com/landing/smile/'; my $regex = qr/First Name[\s\S](?<firstname>.*)[\s\S]Last Name[\s\S](?<lastname>.*)[\s\S]Phone[\s\S](?<phone>.*)[\s\S]E-Mail[\s\S](?<email>.*)[\s\S]*age group\?[\s\S](?<agegroup>.*)[\s\S]*seeing things up close[\s\S](?<farsightedness>.*)[\s\S]*cannot see very well[\s\S](?<astigmatism>.*)[\s\S]*-Glasses[\s\S](?<glasses>.*)[\s\S]*-Contacts[\s\S](?<contacts>.*)[\s\S]*-Reading Glasses[\s\S](?<readingglasses>.*)[\s\S]*following\?-(?<following>.*)[\s\S]*distance without relying on glasses and contact lenses.[\s\S](?<distance>.*)[\s\S]*close without relying on glasses and contact lenses.[\s\S](?<close>.*)[\s\S]*contacts\?[\s\S](?<wouldyourcareerimprove>.*)[\s\S]*Test Score[\s\S](?<testscore>.*)[\s\S]*Entry ID: (?<entryid>.*)[\s\S].*Referrer: (?<referrer>.*)[\s\S]*Host: (?<formhost>.*)/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