Use the `destroy` function to finalize an object by calling its
destructor. The memory of the object is not immediately
deallocated, instead the GC will collect the memory of the object
at an undetermined point after finalization:
class Foo { int x; this() { x = 1; } }
Foo foo = new Foo;
destroy(foo);
assert(foo.x == int.init); // object is still accessible
But I can't understand if D have GC it should remove objects when
their life is finished. When I should to call `destroy`? What
would be if I will not call it?
