hasElaborateCopyConstructor bug?

[Paul Backus]

On Sunday, 2 June 2019 at 06:59:02 UTC, Jonathan M Davis wrote:
> Almost certainly, hasElaborateCopyConstructor should be updated 
> to test for both postblit constructors and copy constructors, 
> since its purpose is to test for whether the type has a 
> user-defined copying function [...] Whether 
> hasElaborateCopyConstructor was the best name is debatable, but 
> it _does_ involve "elaborate" copying, and copy constructors 
> weren't actually in the language at the time. The documentation 
> is wonderfully confusing though in that it talks about copy 
> constructors and then says that a copy constructor is 
> introduced by defining this(this) for a struct. So, it 
> basically calls a postblit constructor a copy constructor.

I've made the mistake in the past of trying to use 
hasElaborateCopyConstructor to test for the presence of 
__xpostblit, and I'm sure I'm not the only one. The name is quite 
misleading--even more so now that D has real copy constructors.

If std.v2 ever materializes, we'll have an opportunity to fix 
papercuts like this. Until then, my preferred workaround is to 
use a renaming import:

import std.traits: hasNontrivialCopy = 
hasElaborateCopyConstructor;