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use disjoint_impls::disjoint_impls;
pub trait Dispatch {
type Group;
}
trait A {}
pub enum GroupA {}
impl A for u16 {}
impl Dispatch for u16 {
type Group = GroupA;
}
impl A for i16 {}
impl Dispatch for i16 {
type Group = GroupA;
}
pub enum GroupB {}
impl Dispatch for i32 {
type Group = GroupB;
}
impl Dispatch for u32 {
type Group = GroupB;
}
disjoint_impls! {
pub trait Kita<U: From<u8> = u32> {
const NAME: &'static str;
}
impl<U: Dispatch<Group = GroupA> + A, T> Kita<U> for T
where
U: From<u8>,
{
const NAME: &'static str = "Blanket A";
}
impl<U: Dispatch<Group = GroupB> + From<u8>, T> Kita<U> for T {
const NAME: &'static str = "Blanket B";
}
}
/*
pub trait Kita<U: From<u8> = u32> {
const NAME: &'static str;
}
const _: () = {
pub trait Kita0<
_TŠČ1: ?core::marker::Sized,
_TŠČ0: From<u8> = u32,
>: Kita<_TŠČ0> {
const NAME_šč: &'static str;
}
impl<U: Dispatch<Group = GroupA> + A, T> Kita0<GroupA, U> for T
where
U: From<u8>,
{
const NAME_šč: &'static str = "Blanket A";
}
impl<U: Dispatch<Group = GroupB> + From<u8>, T> Kita0<GroupB, U> for T {
const NAME_šč: &'static str = "Blanket B";
}
impl<_TŠČ0, _TŠČ1> Kita<_TŠČ0> for _TŠČ1
where
_TŠČ0: From<u8>,
_TŠČ0: From<u8>,
_TŠČ0: Dispatch,
Self: for<'_dšč> Kita0<<_TŠČ0 as Dispatch>::Group, _TŠČ0>,
{
const NAME: &'static str = <Self as Kita0<
<_TŠČ0 as Dispatch>::Group,
_TŠČ0,
>>::NAME_šč;
}
};
*/
#[test]
fn trait_param_with_extra_bound() {
assert_eq!("Blanket A", <u32 as Kita<u16>>::NAME);
assert_eq!("Blanket A", <u32 as Kita<i16>>::NAME);
assert_eq!("Blanket B", <u32 as Kita<u32>>::NAME);
assert_eq!("Blanket B", <u32 as Kita<i32>>::NAME);
}