# std::move_iterator<Iter>::operator*,->

From cppreference.com
< cpp‎ | iterator‎ | move iterator

| (1) |
reference operator* () const; |  | (since C++11) (until C++17)
constexpr reference operator* () const; |  | (since C++17)
| (2) |
pointer operator->() const; |  | (since C++11) (until C++17)
constexpr pointer operator->() const; |  | (since C++17) (deprecated in C++20)

Returns an rvalue-reference or pointer to the current element.

1) Equivalent to static_cast<reference>(*base()) (until C++20)ranges::iter_move(base()) (since C++20).
2) Equivalent to `base()`.

### Parameters

(none)

### Return value

1) Rvalue-reference to the current element or its copy.
2) Copy of the underlying iterator. A pointer to the current element is eventually returned if -> is directly used.

### Notes

Note that (2) eventually returns a pointer if -> is directly used. When dereferencing a pointer the returned value is an lvalue. This may lead to unintended behavior.

### Example

Run this code

    #include <iomanip>
    #include <iostream>
    #include <iterator>
    #include <string>
    #include <vector>

    void print(auto rem, auto const& v)
    {
        for (std::cout << rem; auto const& e : v)
            std::cout << quoted(e) << ' ';
        std::cout << '\n';
    }

    int main()
    {
        std::vector<std::string> p{"alpha", "beta", "gamma", "delta"}, q;
        print("1) p: ", p);
        for (std::move_iterator it{p.begin()}, end{p.end()}; it != end; ++it)
        {
            it->push_back('!'); // calls -> string::push_back(char)
            q.emplace_back( *it );
        }
        print("2) p: ", p);
        print("3) q: ", q);

        std::vector v{1,2,3};
        std::move_iterator it{v.begin()};
        // *it = 13; // error: using rvalue as lvalue
    }

Output:

    1) p: "alpha" "beta" "gamma" "delta"
    2) p: "" "" "" ""
    3) q: "alpha!" "beta!" "gamma!" "delta!"

### Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR | Applied to | Behavior as published | Correct behavior
--- | --- | --- | ---
LWG 2106 | C++11 | dereferencing a `move_iterator` could return a dangling reference if the dereferencing the underlying iterator returns an prvalue | returns the object instead

### See also

operator[] (C++11) | accesses an element by index (public member function)

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