[lucic71]

std::pair::get is defined as:

template< std::size_t I, class T1, class T2 >
typename std::tuple_element<I, std::pair<T1,T2> >::type&
    get( std::pair<T1, T2>& p ) noexcept;

Our rules wrote individual versions for get<0> and get<1>. This PR adds the generic version get<N> as declared by the standard.

This PR also adds get for array and translates tuple_element.

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Rust does not allow writing a rule as get<N>(a0: (T1, T2)) { return a.N } with N = {0, 1}. So we need libcc2rs support for this. TupleElement is the translation of std::tuple_element and TupleGet uses TupleElement to translate std::get.

[nunoplopes]

(conflict)