Parse mailbox headers in PHP

composer.json

{
  "require": {
    "ext-imap": "*",
    "swiftmailer/swiftmailer": "~5.0"
  }
}

parseMailboxList.php

<?php 

/**
 * @param string $value The value of a mailbox header in wire format
 *
 * @throws \Swift_RfcComplianceException if the header cannot be parsed without error
 *
 * @return array suitable for \Swift_Message::setTo et. al.
 */
function parseMailboxList($value)
{
    imap_errors(); // this clears the error memory
    $addresses = array();

    $parsed = imap_rfc822_parse_adrlist($value, '');

    if ($errors = imap_errors()) {
        throw new \Swift_RfcComplianceException(reset($error));
    }

    foreach ($parsed as $i) {
        if (empty($i->host) || empty($i->mailbox)) {
            continue;
        }

        $addresses["{$i->mailbox}@{$i->host}"] = isset($i->personal) ? $i->personal : null;
    }

    return $addresses;
}