std::ranges::view_interface<D>::operator[]
From cppreference.com
< cpp | ranges | view interface
C++
Feature test macros (C++20)
Concepts library (C++20)
Metaprogramming library (C++11)
Ranges library (C++20)
Filesystem library (C++17)
Concurrency support library (C++11)
Execution control library (C++26)
Ranges library
(C++23)(C++23)
(C++26)(C++26)
(C++23)(C++23)
(C++26)(C++26)
(C++26)(C++26)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)
(C++23)(C++23)
(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
(C++23)(C++23)
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