std::data
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                    | Defined in header  <iterator> | ||
| template <class C>  constexpr auto data(C& c) -> decltype(c.data()); | (1) | (since C++17) | 
| template <class C>  constexpr auto data(const C& c) -> decltype(c.data()); | (2) | (since C++17) | 
| template <class T, std::size_t N>  constexpr T* data(T (&array)[N]) noexcept; | (3) | (since C++17) | 
| template <class E> constexpr const E* data(std::initializer_list<E> il) noexcept; | (4) | (since C++17) | 
Returns a pointer to the block of memory containing the elements of the container.
1,2) returns c.data()
3) returns array
4) returns il.begin()
| Contents | 
[edit] Parameters
| c | - | a container with a data() method | 
| array | - | an array of arbitrary type | 
| il | - | an initializer list | 
[edit] Return value
A pointer to the block of memory containing the elements of the container.
[edit] Exceptions
3,4) 
noexcept specification:  
noexcept
  [edit] Notes
In addition to being included in <iterator>, std::data is guaranteed to become available if any of the following headers are included: <array>, <deque>, <forward_list>, <list>, <map>, <regex>, <set>, <string>, <unordered_map>, <unordered_set>, and <vector>.
[edit] Possible implementation
| First version | 
|---|
| template <class C> constexpr auto data(C& c) -> decltype(c.data()) { return c.data(); } | 
| Second version | 
| template <class C> constexpr auto data(const C& c) -> decltype(c.data()) { return c.data(); } | 
| Third version | 
| template <class T, std::size_t N> constexpr T* data(T (&array)[N]) noexcept { return array; } | 
| Fourth version | 
| template <class E> constexpr const E* data(std::initializer_list<E> il) noexcept { return il.begin(); } | 
[edit] Example
| This section is incomplete Reason: no example | 


