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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 Dispatch for [u32; 0] {
type Group = GroupA;
}
pub enum GroupB {}
impl Dispatch for u32 {
type Group = GroupB;
}
impl Dispatch for [i32; 1] {
type Group = GroupB;
}
disjoint_impls! {
pub trait Kita<U>: Dispatch {
const NAME: &'static str;
}
impl<T: Dispatch<Group = GroupA>> Kita<T> for T {
const NAME: &'static str = "Blanket A";
}
impl<R, const N: usize> Kita<*mut Self> for [R; N]
where
Self: Dispatch<Group = GroupA>,
{
const NAME: &'static str = "Blanket A";
}
impl<R, C> Kita<C> for R
where
Self: Dispatch<Group = GroupB>,
{
const NAME: &'static str = "Blanket B";
}
}
/*
pub trait Kita<U>: Dispatch {
const NAME: &'static str;
}
const _: () = {
pub trait Kita0<_TŠČ1: ?Sized, _TŠČ0>: Kita<_TŠČ0> {
const NAME_šč: &'static str;
}
impl<T: Dispatch<Group = GroupA>> Kita0<GroupA, T> for T {
const NAME_šč: &'static str = "Blanket A";
}
impl<R, const N: usize> Kita0<GroupA, *mut [R; N]> for [R; N]
where
[R; N]: Dispatch<Group = GroupA>,
{
const NAME_šč: &'static str = "Blanket A";
}
impl<R, C> Kita0<GroupB, C> for R
where
R: Dispatch<Group = GroupB>,
{
const NAME_šč: &'static str = "Blanket B";
}
impl<_TŠČ0, _TŠČ1> Kita<_TŠČ0> for _TŠČ1
where
Self: Dispatch,
_TŠČ1: Dispatch,
Self: for<'_dšč> Kita0<<_TŠČ1 as Dispatch>::Group, _TŠČ0>,
{
const NAME: &'static str =
<Self as Kita0<<_TŠČ1 as Dispatch>::Group, _TŠČ0>>::NAME_šč;
}
};
*/
#[test]
fn shared_helper() {
assert_eq!("Blanket A", String::NAME);
assert_eq!("Blanket B", <u32 as Kita<i32>>::NAME);
assert_eq!("Blanket A", <[u32; 0] as Kita<*mut [u32; 0]>>::NAME);
assert_eq!("Blanket B", <[i32; 1] as Kita<*mut [i32; 1]>>::NAME);
}