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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 = GroupB;
}
impl Dispatch1 for u32 {
type Group = GroupB;
}
impl Dispatch2 for u32 {
type Group = GroupB;
}
impl core::fmt::Display for GroupB {
fn fmt(&self, _: &mut core::fmt::Formatter) -> core::fmt::Result {
unimplemented!()
}
}
disjoint_impls! {
pub trait Kita {
const NAME: &str;
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupA>> Kita for T {
const NAME: &str = "Blanket A";
}
impl<T: Dispatch1<Group = GroupB> + Dispatch2<Group: ToString>> Kita for T {
const NAME: &'static str = "Blanket B";
}
}
/*
pub trait Kita {
const NAME: &str;
}
const _: () = {
pub trait Kita0<_TŠČ0: ?core::marker::Sized, _TŠČ1: ?core::marker::Sized>: Kita {
const NAME_šč: &str;
}
impl<T: Dispatch1<Group = GroupA> + Dispatch2<Group = GroupA>> Kita0<GroupA, GroupA>
for T {
const NAME_šč: &str = "Blanket A";
}
impl<
T: Dispatch1<Group = GroupB> + Dispatch2<Group = _TŠČ0>,
_TŠČ0: ?core::marker::Sized + ToString,
> Kita0<_TŠČ0, GroupB> for T {
const NAME_šč: &'static str = "Blanket B";
}
impl<_TŠČ0> Kita for _TŠČ0
where
_TŠČ0: Dispatch2,
_TŠČ0: Dispatch1,
Self: for<'_dšč> Kita0<
<_TŠČ0 as Dispatch2>::Group,
<_TŠČ0 as Dispatch1>::Group,
>,
{
const NAME: &str = <Self as Kita0<
<_TŠČ0 as Dispatch2>::Group,
<_TŠČ0 as Dispatch1>::Group,
>>::NAME_šč;
}
};
*/
#[test]
fn dispatch_on_undefined_assoc_binding() {
assert_eq!("Blanket A", String::NAME);
assert_eq!("Blanket B", u32::NAME);
assert_eq!("Blanket B", i32::NAME);
}