std::ranges::dangling
From cppreference.com
| Defined in header <ranges>
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| struct dangling; |
(since C++20) | |
dangling is a placeholder type and an empty class type, used together with the template aliases ranges::safe_iterator_t and ranges::safe_subrange_t.
When some constrain algorithms that usually return an iterator or a subrange of a Range take a particular rvalue Range argument that does not models exposition-only concept __ForwardingRange, dangling will be returned instead to avoid returning potentially dangling results.
Member functions
std::ranges::dangling::dangling
| constexpr dangling() noexcept = default; |
(1) | |
| template<class... Args> constexpr dangling(Args&&...) noexcept { } |
(2) | |
1)
dangling is trivially default constructible.2)
dangling can be constructed from arguments of arbitrary number and arbitrary non-void type. The construction does not have any side-effect itself.
In other words, after replacing the type (e.g. an iterator type) in a well-formed non-aggregate initialization with dangling, the resulting initialization is also well-formed.
Example
| This section is incomplete Reason: no example |
See also
obtains iterator type or subrange type of a Range which also models __ForwardingRange (alias template) |