I have some trait A I want implemented for a bunch of objects, using generics. For some objects I want to have the trait implemented manually.
I would imagine something like this:
trait A {}
struct Manual {}
struct Generic1 {}
struct Generic2 {}
//etc
impl A for Manual {}
impl<T> a for T where T: !A { }
I believe what you're looking for is specialization; in short it's not possible right now. You can see the current progress on implementing the feature here: