On Tuesday, 10 July 2018 at 10:47:04 UTC, RazvanN wrote:
I managed to put together a first draft of the DIP for adding the copy constructor to the language [1]. If anyone is interested, please take a look. Suggestions and comments about technical aspects and wording are all welcome.
When designing D libraries than lean towards DSL style, I've frequently felt impaired by the lack of implicit conversions in D. In my experience, it's not that all types need to be implicitly convertible to other types. Just being able to mark a few types as implicitly convertible to some other specific types would go a long way to alleviate the limitations I felt. It would also solve problems like an arbitrary limit on the depth of implicit conversions.
I had imagined that maybe one day an implicit keyword could be introduced to mark such permissible implicit conversions. Seeing an implicit "keyword" being introduced here with different semantics than I envisioned makes me even less hopeful that some day such implicit conversions annotations could be introduced. So... maybe consider choosing some other syntactic notation? Besides, the fact that the compiler can implicitly introduce calls to the copy ctor doesn't strike me as something particularly central to the concept, so it seems like an odd choice for something to distinguish a copy ctor.
