c++dword

is it possible to cast Dword to Type Name?

Let's take a look at this kind of code : 

// Return me Dword of int
dword t = GetValueTypeNo<int>();
//here trying to tell to GetValue that my template is int (since t is dword of int)
int test5 = myVector.GetValue<t>("test5");

Of course this kind of code is not working and it's actually useless. But it is possible to do something like that? cast a dword to a type name like int?

Solution

  • If GetValueTypeNo can be made a constexpr function, you can make something like this:

    template<typename T>
constexpr dword GetValueTypeNo() { ... }

template<dword>
struct Type_selector;

template<>
struct Type_selector<dword_value_for_int> {
    using Type = int;
};

template<>
struct Type_selector<dword_value_for_long> {
    using Type = long;
};

...

template<dword type>
using Type = typename Type_selector<type>::Type;

    and then write:

    template<dword type>
Type<type> GetValue(...)
{ ... }

constexpr dword t = GetValueTypeNo<int>();
int test5 = myVector.GetValue<t>("test5");