:sig
DValue DValue::pop()

:params
return value : removed child, or an empty DValue when no child exists

:see
0_DValue
2_DValue_push

:content
Ensures the value is map-shaped, removes the last entry according to `std::map` reverse key order, and returns it. For list-mode values, the next array index is reset to the new size.


:example
DValue list;
list.set_array();
DValue a; a.set("first"); list.push(a);
DValue b; b.set("last"); list.push(b);
DValue popped = list.pop();
print("popped ", popped.to_string(), ", remaining ", list.keys().size(), "\n");