From cppreference.com
basic_const_iterator()requiresstd::default_initializable<Iter>=default; (1) (since C++23)constexprbasic_const_iterator(Iterx); (2) (since C++23)template<std::convertible_to<Iter>U>constexprbasic_const_iterator(basic_const_iterator<U>other); (3) (since C++23)template</*different-from*/<basic_const_iterator>T>requiresstd::convertible_to<T,Iter>constexprbasic_const_iterator(T&&x); (4) (since C++23)Constructs a new iterator adaptor.
1) Default constructor. The underlying iterator is value-initialized.
2) The underlying iterator is initialized with std::move(x).
3) The underlying iterator is initialized with that of other.
4) The underlying iterator is initialized with std::forward<T>(x).
Parameters
x - iterator to adapt other - iterator adaptor to copy Example
See also
assigns another basic_const_iterator
(public member function)