<span> functions

The <span> header includes the following non-member functions that operate on span objects.

Non-member functions	Description
as_bytes	Get a read-only view of the object representation of the elements in the span.
as_writable_bytes	Get a read/write view of the object representation of the elements in the span.

as_bytes

Get a read-only view of the object representation of the elements in the span.

template <class T, size_t Extent>
auto as_bytes(span<T, Extent> s) noexcept;

Parameters

T
The type of the elements in the span.

Extent
The number of elements in the span (if known at compile time), otherwise dynamic_extent indicating that the number of elements isn't known until runtime.

s
The span to get the raw representation of.

Return Value

A span<const byte, S> to the first item stored in the span where S is {reinterpret_cast<const std::byte*>(s.data()), s.size_bytes()}

Example

#include <span>
#include <iostream>

using namespace std;

void main()
{
    int a[] = { 0,1,2 };
    span <int> mySpan(a);
    auto bytes = std::as_bytes(mySpan);
}

as_writable_bytes

If T isn't const, gets a read/write view of the raw byte representation of the elements in the span.

template <class T, size_t Extent>
auto as_writable_bytes(span<T, Extent> s) noexcept;

Parameters

T
The type of the elements in the span.

Extent
The number of elements in the span (if known at compile time), otherwise dynamic_extent indicating that the number of elements isn't known until runtime.

s
The span to get the raw representation of.

Return Value

A span<byte, S> to the first item stored in the span where S is {reinterpret_cast<std::byte*>(s.data()), s.size_bytes()}

Example

#include <span>
#include <iostream>

using namespace std;

void main()
{
    int a[] = { 0,1,2 };
    span <int> mySpan(a);
    auto bytes = as_writable_bytes(mySpan);
}

See also

<span>