std::ranges::view_interface::operator[] - cppreference.com (original) (raw)
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.
Let
derivedbe static_cast<D&>(*this). Equivalent to return ranges::begin(derived)[n];.Same as (1), except that
derivedis static_cast<const D&>(*this).
[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.