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use disjoint_impls::disjoint_impls;
pub trait Dispatch1 {
type Group;
}
pub trait Dispatch2 {
type Group;
}
pub enum GroupA {}
pub enum GroupB {}
impl Dispatch1 for String {
type Group = GroupA;
}
impl Dispatch2 for String {
type Group = GroupA;
}
impl<T> Dispatch1 for Vec<T> {
type Group = GroupA;
}
impl<T> Dispatch2 for Vec<T> {
type Group = GroupB;
}
impl Dispatch1 for i32 {
type Group = GroupB;
}
impl Dispatch2 for i32 {
type Group = GroupA;
}
impl Dispatch1 for u32 {
type Group = GroupB;
}
impl Dispatch2 for u32 {
type Group = GroupB;
}
disjoint_impls! {
pub trait Kita {
const NAME: &'static str;
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupA>> Kita for T {
const NAME: &'static str = "Blanket AA";
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupB>> Kita for T {
const NAME: &'static str = "Blanket AB";
}
impl<T: Dispatch1<Group = GroupB> + Dispatch2> Kita for T {
const NAME: &'static str = "Blanket B*";
}
}
/*
pub trait Kita {
const NAME: &'static str;
}
const _: () = {
pub trait Kita0<_TŠČ0: ?Sized, _TŠČ1: ?Sized>: Kita {
const NAME_šč: &'static str;
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupA>> Kita0<GroupA, GroupA> for T {
const NAME_šč: &'static str = "Blanket AA";
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupB>> Kita0<GroupA, GroupB> for T {
const NAME_šč: &'static str = "Blanket AB";
}
impl<T: Dispatch1<Group = GroupB> + Dispatch2> Kita0<GroupB, <T as Dispatch2>::Group> for T {
const NAME_šč: &'static str = "Blanket B*";
}
impl<_TŠČ0> Kita for _TŠČ0
where
_TŠČ0: Dispatch1,
_TŠČ0: Dispatch2,
Self: for<'_dšč> Kita0<<_TŠČ0 as Dispatch1>::Group, <_TŠČ0 as Dispatch2>::Group>,
{
const NAME: &'static str = <Self as Kita0<
<_TŠČ0 as Dispatch1>::Group,
<_TŠČ0 as Dispatch2>::Group,
>>::NAME_šč;
}
};
*/
#[test]
fn multiple_dispatch_traits() {
assert_eq!("Blanket AA", String::NAME);
assert_eq!("Blanket AB", Vec::<u32>::NAME);
assert_eq!("Blanket B*", u32::NAME);
assert_eq!("Blanket B*", i32::NAME);
}