std::ranges::view_interface<D>::operator[]
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< cpp | ranges | view interface
C++
Ranges library
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std::ranges::view_interface
| Member functions | ||||
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(C++23)
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(C++23)
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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) |
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template
<
ranges::random_access_range R =
const D>
constexpr decltype( auto ) operator[ ] ( ranges::range_difference_t <R> n ) const ; |
(2) | (since C++20) |
The default implementation of operator[] member function obtains the element at the specified offset relative to the beginning iterator, reusing the operator[]
2) Same as (1), except that
derived is
static_cast
<
const D&
>
(
*this)
Parameters
| n | - | position of the element to return |
Return value
The element at offset n relative to the beginning iterator.
Notes
In C++20, no type derived from std::ranges::view_interface in the standard library provides their own operator[]
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
Example
| This section is incomplete Reason: no example |