Question

Is there a way to serialize enums automatically as int? Every time I define a new enum and write

std::stringstream stream;
stream << myenum1;
stream >> myenum2;

the compiler complains that the operators << and >> are not defined. Do you know a way to tell the compiler to treat enums as plain int’s?

What makes the problem harder is that, actually, the serialization is inside a template. Something like this:

template <typename T>
void serialize(const T& value)
{
    std::stringstream stream;
    stream << value;
}

So I cannot add any casts 🙁
Maybe I can specialize it somehow?

Thank you.

Answer 1

You can find out if the type is enum with boost’s TypeTraits (is_enum).

Then you can combine this with enable_if / disable_if:

template <class T>
typename boost::disable_if<boost::is_enum<T> >::type serialize(const T&);

template <class T>
typename boost::enable_if<boost::is_enum<T> >::type serialize(const T&); //use casts here

However, it will not be possible to check if a given value is valid for a given enum (unless you write a specific overload for the given enum type).