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use disjoint_impls::disjoint_impls;
pub trait Dispatch {
type Group;
}
pub enum GroupA {}
impl Dispatch for String {
type Group = GroupA;
}
impl<T> Dispatch for Vec<T> {
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> {
const NAME: &'static str;
}
impl<T, U> Kita<U> for T
where
U: Dispatch<Group = GroupA>,
{
const NAME: &'static str = "Blanket A";
}
impl<T, U: Dispatch<Group = GroupB>> Kita<U> for T {
const NAME: &'static str = "Blanket B";
}
}
/*
pub trait Kita<U> {
const NAME: &'static str;
}
const _: () = {
pub trait Kita0<_TŠČ1: ?core::marker::Sized, _TŠČ0>: Kita<_TŠČ0> {
const NAME_šč: &'static str;
}
impl<T, U> Kita0<GroupA, U> for T
where
U: Dispatch<Group = GroupA>,
{
const NAME_šč: &'static str = "Blanket A";
}
impl<T, U: Dispatch<Group = GroupB>> Kita0<GroupB, U> for T {
const NAME_šč: &'static str = "Blanket B";
}
impl<_TŠČ0, _TŠČ1> Kita<_TŠČ0> for _TŠČ1
where
_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 dispatch_on_different_parameters() {
assert_eq!("Blanket A", <String as Kita<String>>::NAME);
assert_eq!("Blanket B", <Vec::<u32> as Kita<u32>>::NAME);
assert_eq!("Blanket B", <u32 as Kita<u32>>::NAME);
assert_eq!("Blanket B", <i32 as Kita<u32>>::NAME);
}