Feature to get or add value to an associative array.

[ag0aep6g]

On Friday, 20 April 2018 at 09:24:26 UTC, Jonathan M Davis wrote:
> The compiler assumes that a pointer is valid when determining 
> whether code is @safe.
[...]
> Basically, it verifies the @safety of pointers when they're 
> created and then assumes that they're @safe after that.

Can't it do the same for ref returns? Unsafe stuff like returning 
a ref to a local is already disallowed, just like returning a 
pointer to a local. So the compiler checks the safety on 
creation, at least in some cases.

> So, passing around a pointer is perfectly @safe, whereas taking 
> the address of a ref return value to get a pointer is not.

It's still not clear to me how taking the address of a ref return 
is necessarily less safe than using a returned pointer. Do you 
maybe have an example in code that shows the difference?

It seems to me that refs and pointers are very much equivalent. I 
should always be able to turn one into the other.