C++ return different objects

Question

i have a big problem.. I wonna select the Storage Service via a wrapper class. The returning value must be an object within the storage service class. I pasted my current approa

Answer 1

in this code

auto test(int select) {
    if( select == 1)
    {
        return new SQL(); 
    } else {
        return new REDIS();
    }

auto can't be deduced because it only match to exact type. so even if SQL and REDIS inherite from StorageTemplate, StorageTemplate won't be deduced. you need to spécifie the type

StorageTemplate* test(int select) {
    if( select == 1)
    {
        return new SQL(); 
    } else {
        return new REDIS();
    }