DIP 45 - approval discussion

[Andrei Alexandrescu]

On 11/12/13 4:36 PM, deadalnix wrote:
> On Tuesday, 12 November 2013 at 22:45:15 UTC, Andrei Alexandrescu wrote:
>> What are the better ways? Note that most of the time you don't "know"
>> the name of a class - you get it down the wire during some
>> deserialization. So there must be some way to build an object from a
>> token representation of the object.
>>
>
> The serialization is a good example. You'll have to note that if the
> code has been able to serialize the data, it can generate at compile
> time the necessary scafolding to deserialize it.

I think there is some confusion here. We're talking about polymorphic 
creation, i.e. an object comes down the wire and you don't know its type 
a priori. Again: grab MC++D and read the chapter on Factory, it 
clarifies all such stuff.

>> It's not quite trivial - somewhere there has to be a map and
>> registration and lookup and whatnot. I don't see it why it's
>> unbecoming for such functionality to be part of the standard library.
>> I would agree, however, that it's a judgment call whether it should be
>> wired in or provided on demand.
>>
>
> That s why this is a problem to add all that is the core of the language
> when it isn't used often.

That's a good point. I would tend to agree with that. But it doesn't 
make it a misfeature. It's a sensible feature.


Andrei