On Monday, 8 June 2020 at 00:31:10 UTC, Steven Schveighoffer
wrote:
This is a bug, please file. What is likely happening is that
the template is not moving the data to the underlying C call.
-Steve
That is not a bug, it's a shortcoming of garbage-collected
arrays. D arrays are not equipped to deal with non-copyable
values. The ~= has to expect to copy contents of arr, since at
runtime there may be multiple references to it, i.e:
auto storage = [NonCopyable(a), /* .... */];
auto arr = storage[1 .. 3];
arr ~= NonCopyable(n);
This would need to allocate a new array and copy contents of
storage[1 .. 3] into it.
