std::result_of doesn't compile [duplicate]

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• Where and why do I have to put the “template” and “typename” keywords? 6 answers

I'm trying to use std::result_of to determine the return type of a callable object:

template <typename T>
std::result_of<T()>::type CallableWrapper(T callableObj) {
    return callableObj();
}

Somewhere else in the code:

auto i = CallableWrapper([](){return 1;});

This code doesn't compile for some reason. I will appreciate if someone would tell me why.