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#include <utility>
#include <concepts>
#include <string>
template <typename Type>
concept ConstDereferenceable =
requires(Type type)
{
{ *type } -> std::same_as<int const &>;
// { *type } -> std::convertible_to<int const &>;
};
//=
template <typename Type>
concept Dereferenceable =
requires(Type type)
{
{ *type } -> std::same_as<int &>;
};
//iterable
struct Iterable
{
Iterable &operator++();
Iterable operator++(int);
int const &operator*() const;
int &operator*();
};
//=
template <typename Type>
concept InIterator =
ConstDereferenceable<Type>;
template <InIterator Type>
void inFun(Type tp)
{}
template <typename Type>
concept OutIterator =
Dereferenceable<Type>;
template <OutIterator Type>
void outFun(Type tp)
{}
int main()
{
inFun(Iterable{});
outFun(Iterable{});
}
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