Answered getTree

$c = $modx->getTree(0, 10);
print_r($c, true); // returns empty

return print_r($c, true);

$output = print_r($c, true);
return $output;

$c = $modx->getTree(0, 10);
$modx->log(modX::LOG_LEVEL_DEBUG, '[mySnippet] was called with the following properties: ' . print_r($c, true)); //returns nothing

$c = $modx->getTree(0, 10);
return print_r($c, true);

\core\model\modx\modx.class.php : 1611) [OnBeforeDocFormSave]Array
(
)

Array ( [1] => Array ( [11] => 11 [8] => 8 [5] => 5 [3] => 3 [9] => 9 [10] => Array ( [7] => 7 [2] => 2 [15] => 15 ) [4] => 4 ) [6] => 6 [13] => 13 [14] => 14 [16] => 16 [17] => 17 [18] => 18 [19] => 19 [20] => 20 [21] => 21 [22] => 22 [23] => 23 [24] => 24 [25] => 25 [26] => 26 [27] => 27 [28] => 28 [29] => 29 [30] => 30 [31] => 31 [32] => 32 [39] => 39 [33] => 33 [40] => 40 [34] => 34 [41] => 41 [35] => 35 [42] => 42 [36] => 36 [43] => 43 [37] => 37 [44] => 44 [38] => 38 [45] => 45 [46] => 46 [47] => 47 [48] => 48 [49] => 49 [50] => 50 [51] => 51 )

$c = $modx->getChildIds(0,$set,array('context' => 'web'));