std::inplace_vector<T,N>::data
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< cpp | container | inplace vector
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Tables
std::inplace_vector
inplace_vector::data
constexpr T* data() noexcept;
(1)
(since C++26)
constexpr const T* data() const noexcept;
(2)
(since C++26)
Returns a pointer to the underlying array serving as element storage. The pointer is such that range [data(), data() + size()) is always a valid range
If *this is empty, data() is not dereferenceable.
Contents
[edit] Return value
Pointer to the underlying element storage. For non-empty containers, the returned pointer compares equal to the address of the first element, that is data() == std::addressof (front()) is true.
[edit] Complexity
Constant.
[edit] Notes
If *this is empty, data() may or may not return a null pointer.
[edit] Example
Run this code
#include <cstddef> #include <iostream> #include <span> #include <inplace_vector> void pointer_func(const int* p, std::size_t size) { std::cout << "data = "; for (std::size_t i = 0; i < size; ++i) std::cout << p[i] << ' '; std::cout << '\n'; } void span_func(std::span <const int> data) // since C++20 { std::cout << "data = "; for (const int e : data) std::cout << e << ' '; std::cout << '\n'; } int main() { std::inplace_vector <int, 4> container{1, 2, 3, 4}; // Prefer container.data() over &container[0] pointer_func(container.data(), container.size()); // std::span is a safer alternative to separated pointer/size. span_func({container.data(), container.size()}); }
Output:
data = 1 2 3 4 data = 1 2 3 4