pop method
Implementation
void pop(String name) {
var state = _stateMap['$name@0'];
if (state != null && state is ReduxStateItem) {
if (_stackMap[name] != null) {
int index = _stackMap[name]!;
_stateMap.remove('$name@$index');
index -= 1;
if (index >= 0) {
_stackMap[name] = index;
} else {
_stackMap.remove(name);
}
}
}
}