This class can be used to display a PHP variable in collapsible tree.
It takes the value of a PHP variable of either the types of integer, string, object, array, etc, and displays it as a nested tree.
The class can traverse arrays and objects recursively. It can also limit the of the depth of the tree when display arrays or objects to avoid infinite loops while display variables that are part of circular references.
For objects, it shows the visibility qualifier: private, protected, public. It can also show an object hash, to denote distinct objects.