Move only C++ code example introduced by Ivan Čukić

move-only.h

#include <type_traits> // is_nothrow_constructible, is_nothrow_assignable
                       // is_nothrow_convertible, is_constructible
                       // is_assignable, is_convertible
#include <memory>      // make_unique
#include <string>      // operator""s

using namespace std::string_literals;

namespace detail {

template <typename T, typename U>
inline constexpr bool linear_usable_as_v =
  std::is_nothrow_constructible_v<T, U> &&
  std::is_nothrow_assignable_v<T&, U> &&
  std::is_nothrow_convertible_v<U, T>;

template <typename T, typename U>
inline constexpr bool linear_unusable_as_v =
  !std::is_constructible_v<T, U> &&
  !std::is_assignable_v<T&, U> &&
  !std::is_convertible_v<U, T>;

} // detail

template <typename T>
concept Linear =
  std::is_nothrow_destructible_v<T> &&
  detail::linear_usable_as_v<T, T> &&
  detail::linear_usable_as_v<T, T&&> &&
  detail::linear_unusable_as_v<T, T&> &&
  detail::linear_unusable_as_v<T, const T&> &&
  detail::linear_unusable_as_v<T, const T>;

auto main() -> int {
  Linear auto ptr = std::make_unique<int>();
  // Linear auto str = "This is literal std::string"s; // error
}

The full talk can be found here.