Custom attributes (again)

[Piotr Szturmaj]

Jacob Carlborg wrote:
> I would like to have the possibility to attach attributes to types and
> parameters as well. Some think like this:
>
> class Bar
> {
> @not_null(Foo) bar (@custom int a) {}
> }
>
> Where @not_null is attached to "Foo" and @custom is attached to "a".

Do you mean return type? I think your syntax has some serious 
disadvantages. Consider parameters and multiple attributes.

For return types I'd like to see something like this:

@return: not_null
@return: MyAttr("foo")
Foo bar(@custom int a) {}

This is similar to C#'s [return: MyAttr]. Alternatively it might be:

@return(not_null)
@return(MyAttr("foo"))