Email regex?

Demonstrating why email regexs are (mostly) poor.
Important notes
Email Validation (syntax/format only) is frequently a hotly discussed topic on forums, irc channels and blogs. Some people believe that to be "correct" your pattern should be RFC 822/2822 complient, others fall into the take anything camp. Personally, I believe a more liberal approach is necessary - the spirit of RFCs is "Be strict in what you send and liberal in what you receive".
Many email addresses might not be strictly to RFC pattern spec, but they work just fine, and in these days of multibyte characters and international character sets, the picture becomes a lot more complicated.
Matrix of Emails against Email validation checkers:

Key: * indicates deviation from the "validity" of the email
Key: Y* indicates test is lax and would let an invalid email through
Key: N* indicates test is too strict and could potentially block a valid email address (more serious than an over-permissive Y*)
Input
Valid?
pgregg's validate_email
function
rfc822
6345 chars
arpad
71 chars
Rejected
42 chars
jome
13 chars
Skiz
42 chars
Lazesharp
160 chars
Shadda
28 chars
Shai-Tan
33 chars
DaSourcerer
223 chars
Slynderdale
72 chars
cronus_
46 chars
asonge
256 chars
php-filter_var
function
arpad2
140 chars
NiteLiteW
120 chars
asonge2
221 chars
HM2K
4020 chars
HM2K 2
96 chars
arpad3
225 chars
archtech
81 chars
dev.to/devlorenzo
71 chars
php-filter_validate_email
533 chars
stevew
84 chars
Jan Goyvaerts http://chris.602.org/temp/email_regex_preg.txt
6353 chars
dominicsayers is_email
function
avataojs
150 chars
powerni
21 chars
'name.lastname@domain.com'
N *
'name+subaddr@domain.com'
N *
'.@'
Y *
'a@b'
Y *
'@bar.com'
Y *
'@@bar.com'
Y *
'a@bar.com'
N *
'aaa.com'
Y *
'aaa@.com'
Y *
'aaa@.123'
Y *
'aaa@[123.123.123.123]'
N *
'aaa@[123.123.123.123]a'
Y *
'aaa@[123.123.123.333]'
Y *
'a@bar.com.'
Y *
'a@bar'
Y *
'a-b@bar.com'
N *
'+@b.c'
Y *
'+@b.com'
N *
'a@-b.com'
Y *
'a@b-.com'
Y *
'-@..com'
Y *
'-@a..com'
Y *
'a@b.co-foo.uk'
N *
'"hello my name is"@stutter.com'
N *
'"Test \"Fail\" Ing"@example.com'
N *
'valid@special.museum'
'invalid@special.museum-'
Y *
'shaitan@my-domain.thisisminekthx'
N *
'test@...........com'
Y *
'foobar@192.168.0.1'
Y *
'"Abc\@def"@example.com'
N *
'"Fred Bloggs"@example.com'
N *
'"Joe\Blow"@example.com'
N *
'"Abc@def"@example.com'
N *
'customer/department=shipping@example.com'
N *
'$A12345@example.com'
N *
'!def!xyz%abc@example.com'
N *
'_somename@example.com'
'Test \ Folding \ Whitespace@example.com'
N *
'HM2Kinsists@(that comments are allowed)this.is.ok'
N *
'user%uucp!path@somehost.edu'
N *
'user@domain.NORTHWESTERNMUTUAL'
N *
'punycode@domain.XN--VERMGENSBERATUNG-PWB'
N *
'cristian_likes_unscores@domain.com'
'cristian_underscore_in_domain@dom_ain.com'
Y *
'user@رسيل.السعودية'
N *
'测试4@ua-test.世界'
N *
'用户@例子.广告'
N *
'अजय@डाटा.भारत '
N *
'квіточка@пошта.укр'
N *
'χρήστης@παράδειγμα.ελ'
N *
'Dörte@Sörensen.example.com'
N *
'коля@пример.рф'
N *
Total differences

<?php
/*
 * Source: http://www.pgregg.com/projects/php/code/showvalidemail.php
 *
 * Email Validation (syntax/format only) is frequently a hotly discussed
 * topic on forums, irc channels and blogs.  Some people believe that to be
 * "correct" your pattern should be RFC 822/2822 complient, others fall into
 * the take anything camp.
 * Personally, I believe a more liberal approach is necessary - the spirit of
 * RFCs is "Be strict in what you send and liberal in what you receive".
 * Many email addresses might not be strictly to RFC pattern spec, but they
 * work just fine, and in these days of multibyte characters and international
 * character sets, the picture becomes a lot more complicated.
 * 
 * This script was put together to test several different email syntax regex
 * validation patterns that I've come across on my travels - though mostly
 * from the EfNet #php irc channel.
 *
 * Author and Copyright of this code: Paul Gregg, 2002-2021
 * http://www.pgregg.com
 * Copyright of the various patterns remain with the named authors.
 *
 */


include "validate_email.inc.phps";
// is_email function from http://www.dominicsayers.com/isemail/
include "dominicsayers.php";


echo <<<EOPAGETOP
<html><head>
 <title>Email regex?</title>
    <style type="text/css">
        * { 
            margin: 10px;
            padding: 2px;
        }
        body {
            background: #f7f7f7;
            //font-size: 12px;
            font-family: tahoma;
        }
        table.file_list {
            border: solid 1px #ccc;
            width: 95%;
            font-size: 12px;
            margin: auto;
        }
        table.file_list td {
            padding: 3px;
        }
        table.file_list .a td {
            background: #eee;
        }
        table.file_list .b td {
            background: #f7f7f7;
        }
        table.file_list .header td {
            background: #ddd;
            font-weight: bold;
        }
        table.file_list .N {
            font-weight: bold;
                }
        table.file_list .Y {
            //font-weight: bold;
                }
    </style>
</head>
<body>
<p>Demonstrating why email regexs are (mostly) poor.</p>
<p><b>Important notes</b>
<br> Email Validation (syntax/format only) is frequently a hotly discussed
 topic on forums, irc channels and blogs.  Some people believe that to be
 "correct" your pattern should be RFC 822/2822 complient, others fall into
 the take anything camp.
 Personally, I believe a more liberal approach is necessary - the spirit of
 RFCs is "Be strict in what you send and liberal in what you receive".
 <br>Many email addresses might not be strictly to RFC pattern spec, but they
 work just fine, and in these days of multibyte characters and international
 character sets, the picture becomes a lot more complicated.
</p>
EOPAGETOP;



$emailregex = array (
    'pgregg\'s <a href="validate_email.inc.phps">validate_email</a>'     =>  'Function:ValidateEmail',
    'rfc822'     =>  '#'.perl_rfc822().'#',
    'arpad'           =>  '/[^@]@(?:(?:[a-z\d-]+\.)+[a-z\d]{2,6}|\[(?:\d{1,3}\.){3}\d{1,3}\])\z/si',
    'Rejected'        =>  '/[A-Z0-9._%-]+@[A-Z0-9._%-]+\.[A-Z]{2,4}/i',
    'jome'            =>  '#^.+@.+\..+$#',
    'Skiz'            =>  '/^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/',
    'Lazesharp'       =>  "#^[\w.%-]+ @ [\w.%-]+ (com|net|org|gov|edu|mil|int|arpa|aero|biz|coop|info|museum|name|pro|asia|cat|jobs|mail|mobi|post|tel|travel|xxx|co|me) (\.[A-Z]{2})? $#ix",
    'Shadda'          =>  "/^\w+@\w+(\.\w{2,3})*\.\w+$/",
    'Shai-Tan'        => "/^\S+@[\w\d.-]{2,}\.[\w]{2,6}$/iU",
    'DaSourcerer'     => '/^("?)(?i:[a-z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\|\}~]+[a-z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\|\}~\.]*[a-z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\|\}~]+)\\1@(?i:[a-z][a-z0-9\-]+\.)+([a-z]{2}|com|org|net|biz|info|name|aero|biz|info|jobs|museum|name)$/',
    'Slynderdale'     => '#^[a-z0-9.!\#$%&\'*+-/=?^_`{|}~]+@([0-9.]+|([^\s\'"<>]+\.+[a-z]{2,6}))$#si',
    'cronus_'         => "#\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*#",
    'asonge'          => "/^[\w!#$%&\'*+-\/=?^_`{|}~]+(?:\.[\w!#$%&\'*+-\/=?^_`{|}~]+)*@(?:(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)|(?:[a-z0-9-]+\.)+(?:arpa|com|edu|gov|int|mil|net|org|biz|info|name|pro|aero|coop|museum|[a-z]{2}))$/i",
    #'zfw_isEmail'     => 'Function:zfw_isEmail',
    'php-filter_var'  => 'Function:php_filter_var',
    'arpad2'          => '/^\s*[\w+." -]+@(?:(?:[a-z\d]+(?:-[a-z\d]+)*\.)+[a-z\d]{2,6}|\[(?:(25[0-5]|2[0-4]\d|[01]?\d?\d)\.){3}(25[0-5]|2[0-4]\d|[01]?\d?\d)\])\s*$/si',
    'NiteLiteW'       => "#^[a-z0-9,!\#\$%&'\*\+/=\?\^_`\{\|}~-]+(\.[a-z0-9,!\#\$%&'\*\+/=\?\^_`\{\|}~-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*\.([a-z]{2,})$#",
    'asonge2'         => '/^(?:[a-z0-9!#$%*\/?|^{}`~&\'+=_.-]+|"(?:(?:\\\\\\\\)*\\\\"|[^\\\\"]+)*")@(?:(\[)(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(?(1)\]|)|(?:(?:[a-z0-9]+(?:-[a-z0-9]+)*)+\.)+[a-z]{2,6})$/i',
    'HM2K'            => '/^((?:(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:\x2e(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+)*)(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|[\x21\x23-\x5b\x5d-\x7e])|(?:\x5c[\x01-\x09\x0b\x0c\x0e-\x7f]|(?:\x5c[\x00-\x7f]))))*(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|[\x21\x23-\x5b\x5d-\x7e])|(?:\x5c[\x01-\x09\x0b\x0c\x0e-\x7f]|(?:\x5c[\x00-\x7f]))))*(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?))(?:\x2e(?:(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|[\x21\x23-\x5b\x5d-\x7e])|(?:\x5c[\x01-\x09\x0b\x0c\x0e-\x7f]|(?:\x5c[\x00-\x7f]))))*(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x22(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)))*))\x40(?:(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:\x2e(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+)*)(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x5b(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|[\x21-\x5a\x5e-\x7e])|(?:\x5c[\x01-\x09\x0b\x0c\x0e-\x7f]|(?:\x5c[\x00-\x7f]))))*(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?\x5d(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)|(?:(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?)(?:\x2e(?:(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?(?:[\x41-\x5a\x61-\x7a]|[\x30-\x39]|[\x21\x23-\x27\x2a\x2b\x2d\x2f\x3d\x3f\x5e\x5f\x60\x7b-\x7e])+(?:(?:(?:[\x20\x09]*(?:\x0d\x0a))?[\x20\x09]+)|(?:[\x20\x09]+(?:(?:\x0d\x0a)[\x20\x09]+)*))?))*)))$/',
    'HM2K 2'          => '/^[\w!#$%&\'*+\/=?^`{|}~.-]+@(?:[a-z\d][a-z\d-]*(?:\.[a-z\d][a-z\d-]*)?)+\.(?:[a-z][a-z\d-]+)$/iD',
    'arpad3'          =>  '/^(?:"(?:\\\\.|[^"])*"|[^@]+)@(?=[^()]*(?:\([^)]*\)[^()]*)*\z)(?![^ ]* (?=[^)]+(?:\(|\z)))(?:(?:[a-z\d() ]+(?:[a-z\d() -]*[()a-z\d])?\.)+[a-z\d]{2,6}|\[(?:(?:1?\d\d?|2[0-4]\d|25[0-4])\.){3}(?:1?\d\d?|2[0-4]\d|25[0-4])\]) *\z/si',
    'archtech'        => '/^[\w%.\'!#$&*+\/=?^`{|}~-]{1,64}@(?:[a-z\d][a-z\d-]+)+(?:\.[a-z\d][a-z\d-]+)+$/iD',
    'dev.to/devlorenzo'         => '/^[a-zA-Z0-9.!#$%&\'*+\/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/',

    'php-filter_validate_email' => "/^((\\\"[^\\\"\\f\\n\\r\\t\\v\\b]+\\\")|([\\w\\!\\#\\$\\%\\&\\'\\*\\+\\-\\~\\/\\^\\`\\|\\{\\}]+(\\.[\\w\\!\\#\\$\\%\\&\\'\\*\\+\\-\\~\\/\\^\\`\\|\\{\\}]+)*))@((\\[(((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9])))\\])|(((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9]))\\.((25[0-5])|(2[0-4][0-9])|([0-1]?[0-9]?[0-9])))|((([A-Za-z0-9\\-])+\\.)+[A-Za-z\\-]+))$/",
    'stevew'          => '/(^(?!.*?\.\.)[^.][a-zA-Z0-9_.+-]+[^.]@[^.-][a-zA-Z0-9-\[\]]+\.[a-zA-Z0-9-.\[\]]+$)/',
    'Jan Goyvaerts http://chris.602.org/temp/email_regex_preg.txt'        =>  '/\\A(?:(?:(?:\\r\\n)?[ \\t])*(?:(?:(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*|(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)*\\<(?:(?:\\r\\n)?[ \\t])*(?:@(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*(?:,@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*)*:(?:(?:\\r\\n)?[ \\t])*)?(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*\\>(?:(?:\\r\\n)?[ \\t])*)|(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)*:(?:(?:\\r\\n)?[ \\t])*(?:(?:(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*|(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)*\\<(?:(?:\\r\\n)?[ \\t])*(?:@(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*(?:,@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*)*:(?:(?:\\r\\n)?[ \\t])*)?(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*\\>(?:(?:\\r\\n)?[ \\t])*)(?:,\\s*(?:(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*|(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)*\\<(?:(?:\\r\\n)?[ \\t])*(?:@(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*(?:,@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*)*:(?:(?:\\r\\n)?[ \\t])*)?(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|"(?:[^\\"\\r\\\\]|\\\\.|(?:(?:\\r\\n)?[ \\t]))*"(?:(?:\\r\\n)?[ \\t])*))*@(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*)(?:\\.(?:(?:\\r\\n)?[ \\t])*(?:[^()<>@,;:\\\\".\\[\\] \\x00-\\x1F]+(?:(?:(?:\\r\\n)?[ \\t])+|\\Z|(?=[\\["()<>@,;:\\\\".\\[\\]]))|\\[([^\\[\\]\\r\\\\]|\\\\.)*\\](?:(?:\\r\\n)?[ \\t])*))*\\>(?:(?:\\r\\n)?[ \\t])*))*)?;\\s*))\\z/',

    'dominicsayers <a href="http://www.dominicsayers.com/isemail/" ref="nofollow">is_email</a>'   => 'Function:is_email',
    'avataojs'   => '/^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/',
    'powerni'    => '/^[-a-zA-Z0-9@\._]+$/',

);
/*
$rfc822 = '#' . perl_rfc822() . '#i';
print $rfc822;
Function ValidateEmail4($emailstr) {
    global $rfc822;
    return (bool)preg_match($rfc822, $emailstr);
}
*/

#http://framework.zend.com/issues/browse/ZF-42
Function zfw_isEmail($value)
    {
        /**
         * @todo RFC 2822 (http://www.ietf.org/rfc/rfc2822.txt)
         */
        $atom = '[-a-z0-9!#$%&\'*+/=?^_`{|}~]';
        $domain = '([a-z0-9]([-a-z0-9]*[a-z0-9]+)?)';
        $regex = '^' . $atom . '+' . '(\.' . $atom . '+)*\@(' . $domain . '{1,63}\.)+' . $domain . '{2,63}$';

        if (eregi($regex, $value))
        {
            return $value;
        }

        return false;
    }

Function php_filter_var($value) {
    if(filter_var($value, FILTER_VALIDATE_EMAIL) === FALSE) return false;
    return $value;
}

$tests = array(
    'name.lastname@domain.com'                   => true,
    'name+subaddr@domain.com'                    => true,
    '.@'                                         => false,
    'a@b'                                        => false,
    '@bar.com'                                   => false,
    '@@bar.com'                                  => false,
    'a@bar.com'                                  => true,
    'aaa.com'                                    => false,
    'aaa@.com'                                   => false,
    'aaa@.123'                                   => false,
    'aaa@[123.123.123.123]'                      => true,
    'aaa@[123.123.123.123]a'                     => false, # extra data outside ip
    'aaa@[123.123.123.333]'                      => false, # not a valid IP
    'a@bar.com.'                                 => false,
    'a@bar'                                      => false,
    'a-b@bar.com'                                => true,
    '+@b.c'                                      => false, # min 2 char tld
    '+@b.com'                                    => true,
    'a@-b.com'                                   => false,
    'a@b-.com'                                   => false,
    '-@..com'                                    => false,
    '-@a..com'                                   => false,
    'a@b.co-foo.uk'                              => true,
    '"hello my name is"@stutter.com'             => true,
    '"Test \"Fail\" Ing"@example.com'            => true,
    'valid@special.museum'                       => true,
    'invalid@special.museum-'                    => false,
    'shaitan@my-domain.thisisminekthx'           => true, # tld way too long (no longer)
    'test@...........com'                        => false, # ......
    'foobar@192.168.0.1'                         => false, # ip need to be []
    // from reading http://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx
    '"Abc\@def"@example.com'                     => true,
    '"Fred Bloggs"@example.com'                  => true,
    '"Joe\\Blow"@example.com'                    => true,
    '"Abc@def"@example.com'                      => true,
    'customer/department=shipping@example.com'   => true,
    '$A12345@example.com'                        => true,
    '!def!xyz%abc@example.com'                   => true,
    '_somename@example.com'                      => true,
    'Test \\'.chr(10).' Folding \\'.chr(10).' Whitespace@example.com' => true,
    'HM2Kinsists@(that comments are allowed)this.is.ok' => true,
    'user%uucp!path@somehost.edu'                => true,
    'user@domain.NORTHWESTERNMUTUAL'             => true,
    'punycode@domain.XN--VERMGENSBERATUNG-PWB'   => true,
    'cristian_likes_unscores@domain.com'         => true,
    'cristian_underscore_in_domain@dom_ain.com'  => false,
    'user@رسيل.السعودية'                         => true, # https://whatis.techtarget.com/definition/email-address-internationalization-EAI#:~:text=Email%20address%20internationalization%20(EAI)%20is,when%20sending%20and%20receiving%20emails.
    '测试4@ua-test.世界'                          => true,
    '用户@例子.广告'                               => true, # (Chinese, Unicode)
    'अजय@डाटा.भारत   '                             => true, # (Hindi, Unicode)
    'квіточка@пошта.укр'                            => true, # (Ukrainian, Unicode)
    'χρήστης@παράδειγμα.ελ'                         => true, # (Greek, Unicode)
    'Dörte@Sörensen.example.com'                 => true, # (German, Unicode)
    'коля@пример.рф'                               => true, # (Russian, Unicode)
);


echo "<br />\nMatrix of Emails against Email validation checkers:<br />";
echo '<br />Key: * indicates deviation from the "validity" of the email';
echo '<br />Key: Y* indicates test is lax and would let an invalid email through';
echo '<br />Key: <span style="font-weight: bold;">N*</span> indicates test is too strict and could potentially block a valid email address (more serious than an over-permissive Y*)<br /><br />';

// Display the table header row
echo '<table cellpadding=4 cellspacing=0 class="file_list"><tr class="header"><td>Input</td><td>Valid?</td>';
foreach ($emailregex as $submitter => $regex) {
    if (preg_match('/^Function:/', $regex))
        $regexsize = '<br/><i>function</i>';
    else
        $regexsize = '<br/><i>' . strlen($regex) . ' chars</i>';
    echo '<td>', $submitter, $regexsize, '</td>';
}
echo '</tr>';

$errorcount = array();
$rowcount=0;
foreach ($tests as $test => $isvalid) {
    $rowclass = (++$rowcount%2==1 ? 'a' : 'b');
    $isvalidyn = ($isvalid ? 'Y' : 'N');

    echo '<tr class="',$rowclass,'"><td>\'', $test, '\'</td><td>', $isvalidyn, '</td>';
    foreach ($emailregex as $submitter => $regex) {
        if (!isset($errorcount[$submitter])) $errorcount[$submitter] = 0;
        if (preg_match('/^Function:/', $regex)) { // call the function
            list($crap, $func) = explode(':', $regex);
            $result = (call_user_func($func, $test) !== false);
        } else
            $result = (preg_match($regex, $test) > 0);
        $resultyn = $result ? 'Y' : 'N';
        printf('<td class="%s">%s%s%s%s</td>',
          ($result != $isvalid && $result === false) ? 'N' : 'Y',
          '', #($result != $isvalid && $result === false) ? '<b>' : '',
          #$resultyn . '(result='.($result?'true':'false').') (resultyn='.$resultyn.')',
          $resultyn,
          $result != $isvalid ? ' *' : '',
          ($result != $isvalid && $result === false) ? '</b>' : ''
        );
        if ($result != $isvalid) $errorcount[$submitter]++;
    }
    echo '</tr>';
}
// display "error" totals
echo '<tr><td>Total differences</td><td>&nbsp;</td>';
foreach ($emailregex as $submitter => $regex) {
    echo '<td><hr>', $errorcount[$submitter], '</td>';
}
echo '</tr>';
echo "</table><br>";

Function perl_rfc822() {
#rfc822 regex from http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html
    $rfc822 = <<<'EOWTF'
(?:(?:\r\n)?[ \t])*(?:(?:(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t]
)+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:
\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(
?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ 
\t]))*"(?:(?:\r\n)?[ \t])*))*@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\0
31]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\
](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+
(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:
(?:\r\n)?[ \t])*))*|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z
|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)
?[ \t])*)*\<(?:(?:\r\n)?[ \t])*(?:@(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\
r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[
 \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)
?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t]
)*))*(?:,@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[
 \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*
)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t]
)+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*)
*:(?:(?:\r\n)?[ \t])*)?(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+
|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r
\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:
\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t
]))*"(?:(?:\r\n)?[ \t])*))*@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031
]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](
?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?
:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?
:\r\n)?[ \t])*))*\>(?:(?:\r\n)?[ \t])*)|(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?
:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?
[ \t]))*"(?:(?:\r\n)?[ \t])*)*:(?:(?:\r\n)?[ \t])*(?:(?:(?:[^()<>@,;:\\".\[\] 
\000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|
\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>
@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"
(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*))*@(?:(?:\r\n)?[ \t]
)*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\
".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?
:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[
\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*|(?:[^()<>@,;:\\".\[\] \000-
\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(
?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)*\<(?:(?:\r\n)?[ \t])*(?:@(?:[^()<>@,;
:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([
^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\"
.\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\
]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*(?:,@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\
[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\
r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] 
\000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]
|\\.)*\](?:(?:\r\n)?[ \t])*))*)*:(?:(?:\r\n)?[ \t])*)?(?:[^()<>@,;:\\".\[\] \0
00-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\
.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,
;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|"(?
:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*))*@(?:(?:\r\n)?[ \t])*
(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".
\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t])*(?:[
^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\]
]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*\>(?:(?:\r\n)?[ \t])*)(?:,\s*(
?:(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\
".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)(?:\.(?:(
?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[
\["()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t
])*))*@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t
])+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?
:\.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|
\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*|(?:
[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".\[\
]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)*\<(?:(?:\r\n)
?[ \t])*(?:@(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["
()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)
?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>
@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*(?:,@(?:(?:\r\n)?[
 \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,
;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\.(?:(?:\r\n)?[ \t]
)*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\
".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*)*:(?:(?:\r\n)?[ \t])*)?
(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\["()<>@,;:\\".
\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])*)(?:\.(?:(?:
\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z|(?=[\[
"()<>@,;:\\".\[\]]))|"(?:[^\"\r\\]|\\.|(?:(?:\r\n)?[ \t]))*"(?:(?:\r\n)?[ \t])
*))*@(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])
+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\
.(?:(?:\r\n)?[ \t])*(?:[^()<>@,;:\\".\[\] \000-\031]+(?:(?:(?:\r\n)?[ \t])+|\Z
|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*))*\>(?:(
?:\r\n)?[ \t])*))*)?;\s*)
EOWTF;
  return str_replace("\n", '', $rfc822);
}

echo '<font face="courier">';
show_source(__FILE__);