std::ranges::view_interface<D>::operator[]
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template<ranges::random_access_range R = D>
constexpr decltype(auto) operator[]( ranges::range_difference_t <R> n );
(1)
(since C++20)
constexpr decltype(auto) operator[]( ranges::range_difference_t <R> n );
template<ranges::random_access_range R = const D>
constexpr decltype(auto) operator[]( ranges::range_difference_t <R> n ) const;
(2)
(since C++20)
constexpr decltype(auto) operator[]( ranges::range_difference_t <R> n ) const;
The default implementation of operator[] member function obtains the element at the specified offset relative to the beginning iterator, reusing the operator[] of the iterator type.
2) Same as (1), except that
derived is static_cast<const D&>(*this).Contents
[edit] Parameters
n
-
position of the element to return
[edit] Return value
The element at offset n relative to the beginning iterator.
[edit] Notes
In C++20, no type derived from std::ranges::view_interface in the standard library provides their own operator[] member function.
However, following derived types cannot use the default implementations, as they never satisfy random_access_range:
- std::ranges::basic_istream_view
- std::ranges::filter_view
- std::ranges::join_view
- std::ranges::lazy_split_view
- std::ranges::split_view
The inherited operator[] member function is available for std::ranges::empty_view , but a call to it always results in undefined behavior.
[edit] Example
This section is incomplete
Reason: no example
Reason: no example