A function that returns a big string version of var_dump or print_r except it descends into private props and shows things in as compact manner as possible.

dump_walk.php

<?php
if (!function_exists('dump_walk')) {
	/**
	 * This function is like print_r($node, true) but cleaner
	 * @param        $node
	 * @param string $indent_string
	 * @param int    $depth
	 * @param null   $parentType
	 * @return string
	 */
	function dump_walk($node, $indent_string = '    ', $depth = 0, $parentType = null, $objects_shown = []) {
		try {
			$append = '';
			if (is_array($node)) {
				$nodeType = 'array';
			}
			else if (is_object($node)) {
				$nodeType = 'object';
			}
			else {
				$nodeType = 'leaf';
			}
			if (null === $parentType) {
				if ($nodeType !== 'object' && $nodeType !== 'array') {
					if (gettype($node) === 'string') {
						$append .= "Root ($nodeType) '$node'";
					}
					else {
						$append .= "Root ($nodeType) $node";
					}
				}
				else {
					if ($nodeType === 'array') {
						$append .= "Root array(" . count($node) . ")\n";
					}
					else if ($nodeType === 'object') {
						$append .= 'Root object ' . get_class($node) . "\n";
					}
					$depth += 1;
				}
			}
			if ($nodeType === 'array') {
				foreach ($node as $k => $child) {
					$branch = false;
					for ($i = 0; $i < $depth; $i++) {
						$append .= $indent_string;
					}
					if (is_array($child)) {
						$branch = true;
						$childNodeType = "array (" . count($child) . ")";
					}
					else if (is_object($child)) {
						if ($child instanceof \DateTime) {
							$child->setTimezone(new \DateTimeZone('America/Los_Angeles'));
							$childNodeType = 'object ' . get_class($child);
							$child = $child->format("Y-m-d g:i:s a e");
						}
						else if ($child instanceof mysqli) {
							$childNodeType = 'object mysqli' . get_class($child);
						}
						else if ($child instanceof mysqli_result) {
							$childNodeType = 'object mysqli_result';
						}
						else {
							$branch = true;
							$childNodeType = 'object ' . get_class($child);
						}
					}
					else {
						$childNodeType = '(' . gettype($child) . ')';
					}

					if ($branch) {
						$append .= "['$k'] => $childNodeType\n" . dump_walk($child, $indent_string, $depth + 1, $nodeType, $objects_shown);
					}
					else {
						if (gettype($child) === 'string') {
							$append .= "['$k'] => $childNodeType '$child'\n";
						}
						elseif (gettype($child) === 'boolean') {
							$append .= "['$k'] => $childNodeType ".($child?"true":"false")."\n";
						}
						elseif (is_null($child)) {
							$append .= "['$k'] => $childNodeType ".'NULL'."\n";
						}
						elseif( is_object($child) ) {
							// non-branching object, don't try and cast to string
							$append .= "['$k'] => $childNodeType\n";
						}
						else {
							$append .= "['$k'] => $childNodeType $child\n";
						}
					}
				}
			}
			else if ($nodeType === 'object') {
				$reflect = new ReflectionObject($node);
				$props = $reflect->getProperties();

				if (!in_array(spl_object_hash($node), $objects_shown)) {
					$objects_shown[] = spl_object_hash($node);
				}
				else {
					for ($i = 0; $i < $depth; $i++) {
						$append .= $indent_string;
					}
					return "$append"."(...)\n";
				}

				foreach ($props as $prop) {
					$is_static = $prop->isStatic();
					$visibility = $prop->isPrivate() ? 'private:' : ''
					. $prop->isPublic() ? 'public:' : ''
					. $prop->isProtected() ? 'protected:' : '';
					$prop->setAccessible(true);
					for ($i = 0; $i < $depth; $i++) {
						$append .= $indent_string;
					}
					$branch = false;
					$child = $prop->getValue($node);
					if (is_array($child)) {
						$branch = true;
						$childNodeType = "array (" . count($child) . ")";
					}
					else if (is_object($child)) {
						if ($child instanceof \DateTime) {
							$child->setTimezone(new \DateTimeZone('America/Los_Angeles'));
							$childNodeType = 'object ' . get_class($child);
							$child = $child->format("Y-m-d g:i:s a e");
						}
						else if ($child instanceof mysqli) {
							$childNodeType = 'object mysqli' . get_class($child);
						}
						else if ($child instanceof mysqli_result) {
							$childNodeType = 'object mysqli_result';
						}
						else {
							$branch = true;
							$childNodeType = 'object ' . get_class($child);
						}
					}
					else {
						$childNodeType = '(' . gettype($child) . ')';
					}

					if ($branch) {
						$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType\n" . dump_walk($prop->getValue($node), $indent_string, $depth + 1, $nodeType, $objects_shown);
					}
					else {
						if (gettype($child) === 'string') {
							$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType '$child'\n";
						}
						elseif (gettype($child) === 'boolean') {
							$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType ".($child?"true":"false")."\n";
						}
						elseif (is_null($child)) {
							$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType ".'NULL'."\n";
						}
						elseif( is_object($child) ) {
							// non-branching object, don't try and cast to string
							$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType\n";
						}
						else {
							$append .= "->{$prop->getName()}:{$visibility}" . ($is_static ? ':static' : '') . " = $childNodeType $child\n";
						}
					}
				}
			}
			return $append;
		}
		catch (\Exception $e) {
			return 'dump_walk() error: ' . $e->getMessage();
		}
	}
}