Perhaps simpler(?) would be:
$directories = array(
'general_documents' => array(
'file1',
'file2',
'file3'
),
'hr_documents' => array(
'file1',
'file2',
'file3',
'file4'
)
);
Then if you want a list of files in the 'hr_documents' directory:
echo "<ul>\n";
foreach($directories['hr_documents'] as $filename)
{
echo "<li>$filename</li>\n";
}
echo "</ul>\n";