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#![deny(missing_docs)]
use frunk::labelled::Transmogrifier;
use frunk::{HCons, HNil};
use std::marker::PhantomData;
pub enum HEither<H, T> {
Head(H),
Tail(T),
}
pub struct Variant<K, T> {
pub key: &'static str,
pub value: T,
pub name_type_holder: PhantomData<K>,
}
#[macro_export]
macro_rules! variant {
(($($repeated: ty),*), $value: expr) => {
$crate::variant!( ($($repeated),*), $value, concat!( $(stringify!($repeated)),* ) )
};
(($($repeated: ty,)*), $value: expr) => {
$crate::variant!( ($($repeated),*), $value )
};
($name_type: ty, $value: expr) => {
$crate::variant!( $name_type, $value, stringify!($name_type) )
};
($name_type: ty, $value: expr, $name: expr) => {
$crate::Variant::<$name_type,_> {
key: $name,
value: $value,
name_type_holder: std::marker::PhantomData,
}
}
}
impl<TargetHead, TargetTail, SourceHead, SourceTail, HeadIndices, TailIndices, Key>
Transmogrifier<HEither<Variant<Key, TargetHead>, TargetTail>, HCons<HeadIndices, TailIndices>>
for HEither<Variant<Key, SourceHead>, SourceTail>
where
SourceHead: Transmogrifier<TargetHead, HeadIndices>,
SourceTail: Transmogrifier<TargetTail, TailIndices>,
{
#[inline(always)]
fn transmogrify(self) -> HEither<Variant<Key, TargetHead>, TargetTail> {
match self {
HEither::Head(Variant {
value: h, key: k, ..
}) => HEither::Head(variant!(Key, h.transmogrify(), k)),
HEither::Tail(t) => HEither::Tail(t.transmogrify()),
}
}
}
pub enum Void {}
impl Transmogrifier<Void, HNil> for Void {
fn transmogrify(self) -> Void {
match self {}
}
}