php-tcpdf installs outdated code which breaks with " Deprecated: The each() function is deprecated." on PHP version 7.2.7-0ubuntu0.18.04.2

[Carl B.]

I just installed Ubuntu 18.04 LTS Release: 18.04 and the TCPDF packaged with it doesn't work properly with the PHP 7.2.7 which came with the same Ubuntu release:

# apt install php-tcpdf
php-tcpdf is already the newest version (6.2.13+dfsg-1ubuntu1).

# php -v
PHP 7.2.7-0ubuntu0.18.04.2 (cli) (built: Jul 4 2018 16:55:24) ( NTS )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.2.0, Copyright (c) 1998-2018 Zend Technologies
    with Zend OPcache v7.2.7-0ubuntu0.18.04.2, Copyright (c) 1999-2018, by Zend Technologies

gives me this when I try to download a PDF from a website hosted on Ubuntu 18.04 LTS:

Deprecated: The each() function is deprecated. This message will be suppressed on further calls in /usr/share/php/tcpdf/tcpdf.php on line 16542
TCPDF ERROR: Some data has already been output, can't send PDF file

TCPDF was generating a valid PDF for download before the "upgrade" from Ubuntu 16 to Ubuntu 18 replaced PHP with a newer version that deprecates a function which is needed. A forum post at http://www.chronoengine.com/forums/posts/t105654/tcpdf-broken-on-php-7-2 suggests that TCPDF version 6.2.17 contains a fix for this issue, but Ubuntu 18.04 LTS is deploying an older version php-tcpdf 6.2.13+dfsg-1ubuntu1, which simply refuses to play nice with the PHP 7.2.7-0ubuntu0.18.04.2 bundled into the same release of Ubuntu.

[Carl B. (carlb)]

According to https://github.com/elibyy/tcpdf-laravel/issues/37 this might be as simple as editing /usr/share/php/tcpdf/tcpdf.pdf to replace every instance of:

   while (list($id, $name) = each($attr_array[1])) {

with:

   foreach($attr_array[1] as $id => $name) {

Nonetheless, it would be preferable that the distribution install up-to-date (or at least compatible) versions of all packages so that users don't need to make these sort of patches.