How to retrieve mapbox::util::variant value in a templated function

Question

With mapbox::variant (https://github.com/mapbox/variant/blob/master/include/mapbox/variant.hpp), I can do the following:

using variant = mapbox::util::variant<Args...>;
variant<std::string> v;
// do something with v
...
// Get string from v:
std::string s = v.get<std::string>();

But when I try to implement this by a template function, I got compile error:

template <typename T>
T getValue()
{
    variant<T> value{};
    // Get value
    ...
    return value.get<T>();
}

GCC complains:

../utils.hpp:52:23: error: expected primary-expression before '>' token return value.get(); ^ ../utils.hpp:52:25: error: expected primary-expression before ')' token return value.get();

What is wrong with the template function?

Woops, yes, it helps. Please post it as an answer so I can mark it the correct. — Mine, Jan 23 '17 at 13:50

score 1 · Accepted Answer · edited May 23 '17 at 11:52

1

I think you want:

return value.template get<T>();

this answer gives a good/comprehensive description as to why...

edited May 23 '17 at 11:52

Community

1
1

answered Jan 23 '17 at 13:56

Biggy Smith

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How to retrieve mapbox::util::variant value in a templated function

1 Answers1