This is a fairly concise version which does not rely on traditional recursion:
<?php
function array_replace_recursive($base, $replacements)
{
foreach (array_slice(func_get_args(), 1) as $replacements) {
$bref_stack = array(&$base);
$head_stack = array($replacements);
do {
end($bref_stack);
$bref = &$bref_stack[key($bref_stack)];
$head = array_pop($head_stack);
unset($bref_stack[key($bref_stack)]);
foreach (array_keys($head) as $key) {
if (isset($key, $bref) && is_array($bref[$key]) && is_array($head[$key])) {
$bref_stack[] = &$bref[$key];
$head_stack[] = $head[$key];
} else {
$bref[$key] = $head[$key];
}
}
} while(count($head_stack));
}
return $base;
}
?>