and method
Implementation
Condition<EntityT> and(Condition<EntityT> rh) {
if (this is _ConditionGroupAll) {
// no need for brackets
return _ConditionGroupAll<EntityT>(
[...(this as _ConditionGroupAll<EntityT>)._conditions, rh]);
}
return _ConditionGroupAll<EntityT>([this, rh]);
}