Display an array in a readable/hierarchical format

Instead of

print_r($data);

try

print "<pre>";
print_r($data);
print "</pre>";

print("<pre>".print_r($data,true)."</pre>");

I have a basic function:

function prettyPrint($a) {
    echo "<pre>";
    print_r($a);
    echo "</pre>";
}

prettyPrint($data);

EDIT: Optimised function

function prettyPrint($a) {
    echo '<pre>'.print_r($a,1).'</pre>';
}

EDIT: Moar Optimised function with custom tag support

function prettyPrint($a, $t='pre') {echo "<$t>".print_r($a,1)."</$t>";}