What about:
struct json : ::boost::variant<
::std::vector<::std::unique_ptr<json> >,
::std::unordered_map<::std::string, ::std::unique_ptr<json> >,
value
>
{
using variant::variant;
template <typename U>
json& operator=(U&& u)
{
variant::operator=(::std::forward<U>(u));
return *this;
}
};
That would be the solution, except it doesn't work for me with g++ (constructing json out of vector fails because of ambiguous constructor call). Construction from a const reference to such a vector works, but not not from a non-const reference. I have no idea why. In addition, unique_ptr
doesn't work with boost::variant
for me because it's uncopyable (shared_ptr
does work).