Copy Constructor DIP

[Andrei Alexandrescu]

On 7/14/18 5:03 AM, Luís Marques wrote:
> If there is "no other meaning of @implicit" (other than the intersection 
> of those two properties) why don't you just call it something like 
> @copyctor?

I'm totally cool with giving the attribute a more obscure name such as 
@copyctor or anything people want really.

(What follows is a personal opinion.

I think it's better to choose a more general attribute name with reduced 
initial applicability. Then application of said attribute can be 
extended to other functions with ease. In contrast, an obscure attribute 
name is sure to be followed by more obscure attribute names. And don't 
get me started about inventing new syntax.

Regarding the hand-wringing over generality: we have an exceedingly poor 
record of paralysis of analysis, whereby we'd worry that every design 
decision potentially locks us out from all other as-of-yet-unchosen 
design decisions. If history is any indication, this sudden worry about 
vaguely-promising green pastures of the future is a sign of malady. We 
want copy construction. Conflating this with a very general schemata for 
implicit conversion would not be a wise decision in my opinion. I now 
deeply regret ever telling Razvan to mention future possible directions. 
This DIP must do implicit copy constructors and do it well, nothing less 
and nothing more.)


Andrei