How does std::end work on native arrays

Question

In Modern C++, we can use std::end on native arrays. I wanted to ask how does this work to understand the performance considerations for this.

It works [like this](http://en.cppreference.com/w/cpp/iterator/end) — Nicol Bolas, Feb 17 '17 at 07:41
See also Motti's answer [to this related question](http://stackoverflow.com/questions/4108313/how-do-i-find-the-length-of-an-array). — juanchopanza, Feb 17 '17 at 07:42

score 1 · Answer 1 · answered Feb 17 '17 at 07:42

If you have an array called a with size N, then std::end(a) means the same thing as a + N. It doesn't need to do any run-time work to find the size of the array, because the size is known at compile time.

Note that std::end won't work on a pointer. It will only work on an array that has not been decayed to a pointer, so the size information is statically present at the call site.

How does std::end work on native arrays

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