User attributes (was Proposal on improvement to deprecated)

[Jacob Carlborg]

On 2011-10-03 20:22, Piotr Szturmaj wrote:
> Aleksandar Ružičić wrote:
>> What about using an attribute for that?
>
> Looks like a good use case for user defined attributes (I need to write
> DIP on that).
>


> There are of course many other possible use cases like Object/Relational
> Mapping, RPC/Remoting, debugger visualization overrides, hints for the
> GC, etc.
>
> User defined attributes provide a powerful way to extend language
> without constantly upgrading the compiler (and avoiding "too many
> features" in it).
>
> I would love to hear any opinions about general idea of user defined
> attributes in D, not necessarily this particular syntax as it is only
> my loud thinking, though it should show what the whole thing is about.

I would love this see this as well. I think it needs to be accessible at 
runtime too. It should be possible to get the attributes of a class 
through a base class reference and it should return the attributes of 
the runtime type.

I would like to have something similar as this possible as well:

class Foo
{
     @get_set int x;
}

Would insert a getter and setter for "x" like this:

class Foo
{
     int x_;

     int x () { return x_; }
     int x (int x) { return x_ = x; }
}

An attribute should be able to insert something else instead of the 
symbol it applies to, or nothing at all.

-- 
/Jacob Carlborg