$_lazyProps
$_lazyProps :
The Config class relies on LazyProp to store configuration data in a unique way. For example, the database connection is configured by adding a lazily evaluated property: $config->lazy('db', function() { return new PDO( .
.. ); });
Whenever some component need to access the database, the $config->db will be the PDO-instance requested. The connection is, however, not created until the $config->db property is accessed for the first time.