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copied!<p>I advise against writing a general <code>strict_move</code> that is detecting <code>const</code>. I think that is not really what you're looking for. Do you want this to flag a <code>const complex<double></code>, or a const <code>pair<int, int></code>? These types will copy as fast they move. Flagging them would just be an irritant.</p> <p>If you want to do this, I recommend instead checking to see if the type is <code>noexcept MoveConstructible</code>. This will work perfectly for <code>std::string</code>. If the copy constructor of <code>string</code> is accidentally called, it is not noexcept, and therefore will be flagged. But if the copy constructor of <code>pair<int, int></code> is accidentally called, do you really care?</p> <p>Here is a sketch of what this would look like:</p> <pre><code>#include <utility> #include <type_traits> template <class T> typename std::remove_reference<T>::type&& noexcept_move(T&& t) { typedef typename std::remove_reference<T>::type Tr; static_assert(std::is_nothrow_move_constructible<Tr>::value, "noexcept_move requires T to be noexcept move constructible"); static_assert(std::is_nothrow_move_assignable<Tr>::value, "noexcept_move requires T to be noexcept move assignable"); return std::move(t); } </code></pre> <p>I decided to check against <code>is_nothrow_move_assignable</code> as well, as you don't know whether the client is constructing or assigning the lhs.</p> <p>I opted for internal <code>static_assert</code> instead of an external <code>enable_if</code> because I don't expect <code>noexcept_move</code> to be overloaded, and the <code>static_assert</code> will yield a clearer error message when triggered.</p>

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