std::span

17/2/22

c++

std::span is a wrapper for build-in arrays. Build-in arrays have their own syntax and semantics. They can’t be directly assigned one another, can’t pass to or return from a function.

std::span provides range abstraction and class semantics to them, so they’ll behave just like any other std container. This especially useful when we need to pass a build-in array to a function.

Instead of:

void processBuffer(const std::uint8_t *data, const std::size_t size) {
  // ...
}

std::uint8_t data[]{/*...*/};
processBuffer(data, std::size(data));

we can write:

void processBuffer(const std::span<std::uint8_t> buffer) {
  // ...
}

processBuffer(data);

std::spanis C++20 addition but there exist backports even for C++98!