std::from_range, std::from_range_t - cppreference.com (original) (raw)
| Defined in header | | | | ----------------------------------------------------------------------- | | ------------- | | struct from_range_t { explicit from_range_t() = default; }; | | (since C++23) | | inline constexpr std::from_range_t from_range {}; | | (since C++23) |
std::from_range is a disambiguation tag that can be passed to the constructors of the suitable containers to indicate that the contained member is range constructed.
The corresponding type std::from_range_t can be used in the constructor's parameter list to match the intended tag.
Contents
[edit] Standard library
The following standard library types use std::from_range_t type in their constructors:
| Containers library | |
|---|---|
| (constructor)(C++23) | constructs the vector from a range (public member function of std::vector<T,Allocator>) |
| (constructor)(C++26) | constructs the inplace_vector from a range (public member function of std::inplace_vector<T,N>) |
| (constructor)(C++26) | constructs the hive from a range (public member function of Template:cpp/container/hive/title) |
| (constructor)(C++23) | constructs the deque from a range (public member function of std::deque<T,Allocator>) |
| (constructor)(C++23) | constructs the forward_list from a range (public member function of std::forward_list<T,Allocator>) |
| (constructor)(C++23) | constructs the list from a range (public member function of std::list<T,Allocator>) |
| (constructor)(C++23) | constructs the set from a range (public member function of std::set<Key,Compare,Allocator>) |
| (constructor)(C++23) | constructs the map from a range (public member function of std::map<Key,T,Compare,Allocator>) |
| (constructor)(C++23) | constructs the multiset from a range (public member function of std::multiset<Key,Compare,Allocator>) |
| (constructor)(C++23) | constructs the multimap from a range (public member function of std::multimap<Key,T,Compare,Allocator>) |
| (constructor)(C++23) | constructs the unordered_set from a range (public member function of std::unordered_set<Key,Hash,KeyEqual,Allocator>) |
| (constructor)(C++23) | constructs the unordered_map from a range (public member function of std::unordered_map<Key,T,Hash,KeyEqual,Allocator>) |
| (constructor)(C++23) | constructs the unordered_multiset from a range (public member function of std::unordered_multiset<Key,Hash,KeyEqual,Allocator>) |
| (constructor)(C++23) | constructs the unordered_multimap from a range (public member function of std::unordered_multimap<Key,T,Hash,KeyEqual,Allocator>) |
| (constructor)(C++23) | constructs the priority_queue from a range (public member function of std::priority_queue<T,Container,Compare>) |
| (constructor)(C++23) | constructs the queue from a range (public member function of std::queue<T,Container>) |
| (constructor)(C++23) | constructs the stack from a range (public member function of std::stack<T,Container>) |
| (constructor)(C++23) | constructs the flat_set from a range (public member function of std::flat_set<Key,Compare,KeyContainer>) |
| (constructor)(C++23) | constructs the flat_map from a range (public member function of std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>) |
| (constructor)(C++23) | constructs the flat_multiset from a range (public member function of std::flat_multiset<Key,Compare,KeyContainer>) |
| (constructor)(C++23) | constructs the flat_multimap from a range (public member function of std::flat_multimap<Key,T,Compare,KeyContainer,MappedContainer>) |
| Strings library | |
| (constructor)(C++23) | constructs the basic_string from a range (public member function of std::basic_string<CharT,Traits,Allocator>) |
[edit] Notes
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
| __cpp_lib_containers_ranges | 202202L | (C++23) | Tagged constructors to construct from container compatible range |
[edit] Example
#include #include int main() { #ifdef __cpp_lib_containers_ranges auto const range = {0x43, 43, 43}; std::string str{std::from_range, range}; // uses tagged constructor assert(str == "C++"); #endif }