is_email()
Copyright 2008-2011 Dominic Sayers <dominic@sayers.cc>
http://isemail.info
BSD License (http://www.opensource.org/licenses/bsd-license.php)

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How to use is_email()
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1. Add the downloaded file is_email.php to your project
2. In your scripts use it like this:

	require_once 'is_email.php';
	if (is_email($email)) echo "$email is a valid email address";

3. If you want to return detailed diagnostic error codes then you can ask
is_email to do so. Something like this should work:

	require_once 'is_email.php';
	$email = 'dominic@sayers.cc';
	$result = is_email($email, true, true);

	if ($result === ISEMAIL_VALID) {
		echo "$email is a valid email address";
	} else if ($result < ISEMAIL_THRESHOLD) {
		echo "Warning! $email has unusual features (result code $result)";
	} else {
		echo "$email is not a valid email address (result code $result)";
	}

4. Example scripts are in the extras folder

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Version history
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Date       Component    Version Notes
.......... ............ ....... ...............................................
2010-10-18 is_email.php 3.0	Forensic categorization of email validity

2010-10-18 tests.xml    3.0	New schema designed to enhance fault
				identification.

2011-05-23 tests.xml	3.02	tests.php
				Argument no longer passed by reference
				(deprecated)

				Test#32
				Changed domain to c--n.com because g--a.com no
				longer has an MX record.

2010-11-15 meta.xml	3.03    Clarified definition of Valid for numpties

2011-07-14 tests.xml	3.04	Changed my link to http://isemail.info

2013-11-29 tests.xml	3.05	Changed Test #71 from ISEMAIL_RFC5321 to ISEMAIL_DEPREC 
2013-11-29 meta.xml	3.05	Changed category of ISEMAIL_RFC5321_IPV6DEPRECATED to ISEMAIL_DEPREC 		
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