Can C++ tuple element types be conditionally added based on template parameters?

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I'm trying to conditionally add types to a tuple template type based on some compile time condition, as follows:

template <typename T>
class Base { ... }

template <int I>
class Derived : public Base<std::tuple<std::conditional<I % 8 == 0, int,    void>::type,
                                       std::conditional<I % 4 == 0, double, void>::type,
                                       std::conditional<I % 2 == 0, float,  void>::type>>
{ ... }

I understand that this isn't valid code, but conceptually I'm trying to conditionally add types to the tuple's list. I would like the type to be skipped when the conditional resolves to void.

Is there a way to do something like this?

c++ tuples template-meta-programming

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edited Apr 19 at 13:38

Nate

asked Apr 19 at 1:45

NateNate

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