How to check member function for being @disable?

[Jonathan M Davis via Digitalmars-d-learn]

On Tuesday, September 13, 2016 08:28:10 Jonathan M Davis via Digitalmars-d-
learn wrote:
> On Tuesday, September 13, 2016 04:58:38 Uranuz via Digitalmars-d-learn 
wrote:
> > In my code I iterate in CT over class methods marked as @property
> > and I have a probleme that one of methods is @disable. So I just
> > want to skip @disable members. I found possible solution, but
> > it's interesting to we if we have more clear and obvious way to
> > test for @disable without using __traits( compile ) for it?
> > @disable "looks" like attribute but seems that I cant't get it
> > through __traits( getAttributes ) or __traits(
> > getFunctionAttributes ). Maybe we could add something to test for
> > @disable if it's not already exists?
>
> I really don't think that it's going to scale properly to check whether
> something is marked with @disable. The problem is that it propagates. For
> instance, if a struct has a member variable that has default initialization
> disabled via @disable this(); then that struct effectively has @disable
> this(); too even though it doesn't have it explicitly. So, ultimately what
> needs to be tested for is the behavior and not the presence of @disable, and
> that means testing with __traits(compiles, ...). And I would point out that
> most traits test via __traits(compiles, ...) or is(typeof(...)) rather than
> checking for something like an attribute. So, if don't like using
> __traits(compiles, ...) in metaprogramming, your going to get frustrated
> quickly. A large portion of the time, it's exactly the solution to the
> problem.

What would make sense would be creating a trait to test for the @disabled
functionality in queston - e.g. there could be an eponymous template named
something like hasDefaultInitializer (though that name is a bit long) which
indicated whether a type had @disabled this(); or not. Then you can use that
trait in your code rather than using __traits(compiles, ...) all over the
place.

- Jonthan M Davis