Added copy constructors to "Programming in D"

[bauss]

On Thursday, 10 February 2022 at 23:21:50 UTC, Meta wrote:
> On Thursday, 10 February 2022 at 20:34:29 UTC, Walter Bright 
> wrote:
>> On 2/10/2022 12:06 AM, Mathias LANG wrote:
>>> I think an *immediate* improvement we could make to ease 
>>> people's life is to make `auto` peel the outermost qualifier 
>>> level inside functions.
>>> 
>>> So that:
>>> ```D
>>> const int* ptr;
>>> auto p2 = ptr;
>>> static assert(is(typeof(p2) == const(int)*));
>>> ```
>>> 
>>> I really can't think of any downside to it, only upsides:
>>> - It is still predictable / consistent;
>>> - It *might* reduce the number of template instantiations in 
>>> some cases;
>>> - It just flows more naturally... If you want full constness, 
>>> there's still `const`;
>>
>> It sounds sensible to me.
>
> Didn't Scott Meyers cover exactly this in his "the last thing D 
> needs" talk? It seems like a really bad idea.

Well D has already taken the piss on that talk a long time ago.

No offense to D overall, and I still love it.