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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 {
const NAME: &'static str;
fn name() -> &'static str {
"Default blanket"
}
}
impl<T: Dispatch<Group = GroupA>> Kita for T {
const NAME: &'static str = "Blanket A";
}
impl<U: Dispatch<Group = GroupB>> Kita for U {
const NAME: &'static str = "Blanket B";
fn name() -> &'static str {
"Blanket B"
}
}
}
/*
pub trait Kita {
const NAME: &'static str;
fn name() -> &'static str {
"Default blanket"
}
}
const _: () = {
pub trait Kita0<_TŠČ0: ?core::marker::Sized>: Kita {
const NAME_šč: &'static str;
fn name_šč() -> &'static str {
"Default blanket"
}
}
impl<T: Dispatch<Group = GroupA>> Kita0<GroupA> for T {
const NAME_šč: &'static str = "Blanket A";
}
impl<U: Dispatch<Group = GroupB>> Kita0<GroupB> for U {
const NAME_šč: &'static str = "Blanket B";
fn name_šč() -> &'static str {
"Blanket B"
}
}
impl<_TŠČ0> Kita for _TŠČ0
where
_TŠČ0: Dispatch,
Self: for<'_dšč> Kita0<<_TŠČ0 as Dispatch>::Group>,
{
const NAME: &'static str = <Self as Kita0<
<_TŠČ0 as Dispatch>::Group,
>>::NAME_šč;
fn name() -> &'static str {
<Self as Kita0<<_TŠČ0 as Dispatch>::Group>>::name_šč()
}
}
};
*/
#[test]
fn basic() {
assert_eq!("Blanket A", String::NAME);
assert_eq!("Blanket A", Vec::<u32>::NAME);
assert_eq!("Blanket B", u32::NAME);
assert_eq!("Blanket B", i32::NAME);
assert_eq!("Default blanket", String::name());
assert_eq!("Default blanket", Vec::<u32>::name());
assert_eq!("Blanket B", u32::name());
assert_eq!("Blanket B", i32::name());
}