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use std::convert::TryFrom;

pub trait ClonedFrom<T: ?Sized>: Sized {
    fn cloned_from(value: &T) -> Self;
}

pub trait ToCloned<T: ?Sized>: Sized {
    fn to_cloned(&self) -> T;
}

pub trait TryClonedFrom<T: ?Sized>: Sized {
    type Error;

    fn try_cloned_from(value: &T) -> Result<Self, Self::Error>;
}

pub trait TryToCloned<T>: Sized {
    type Error;

    fn try_to_cloned(&self) -> Result<T, Self::Error>;
}

impl<T, U> ClonedFrom<T> for U
where
    T: Clone + ?Sized,
    U: From<T>,
{
    fn cloned_from(value: &T) -> Self {
        U::from(value.clone())
    }
}

impl<T, U> ToCloned<U> for T
where
    U: ClonedFrom<T>,
{
    fn to_cloned(&self) -> U {
        U::cloned_from(self)
    }
}

impl<T, U> TryClonedFrom<T> for U
where
    T: Clone + ?Sized,
    U: TryFrom<T>,
{
    type Error = <U as TryFrom<T>>::Error;

    fn try_cloned_from(value: &T) -> Result<U, Self::Error> {
        <Self as TryFrom<T>>::try_from(value.clone())
    }
}

impl<T, U> TryToCloned<U> for T
where
    U: TryClonedFrom<T>,
{
    type Error = U::Error;

    fn try_to_cloned(&self) -> Result<U, Self::Error> {
        U::try_cloned_from(self)
    }
}

#[cfg(test)]
mod test {
    use super::*;

    #[derive(Clone)]
    struct ItemA {
        a: u64,
        b: String,
    }

    #[allow(dead_code)]
    struct ItemA2 {
        a: u64,
        b: String,
    }

    #[allow(dead_code)]
    struct ItemB {
        a: ItemA,
        b: bool,
    }

    impl ClonedFrom<ItemA> for ItemA2 {
        fn cloned_from(value: &ItemA) -> Self {
            Self {
                a: value.a,
                b: value.b.clone(),
            }
        }
    }

    impl TryClonedFrom<ItemA> for ItemB {
        type Error = ();

        fn try_cloned_from(value: &ItemA) -> Result<Self, Self::Error> {
            Ok(Self {
                a: value.clone(),
                b: true,
            })
        }
    }

    #[test]
    fn cloned_from() {
        let _item_a2 = ItemA2::cloned_from(&ItemA {
            a: 24,
            b: "lol".into(),
        });
    }

    #[test]
    fn cloned_from_self() {
        let _item_a = ItemA::cloned_from(&ItemA {
            a: 24,
            b: "lol".into(),
        });
    }

    #[test]
    fn to_cloned() {
        let item_a = ItemA {
            a: 24,
            b: "lol".into(),
        };
        let _item_a2: ItemA2 = item_a.to_cloned();
    }

    #[test]
    fn to_cloned_self() {
        let item_a = ItemA {
            a: 24,
            b: "lol".into(),
        };
        let _item_a: ItemA = item_a.to_cloned();
    }

    #[test]
    fn try_to_cloned() {
        let item_a = ItemA {
            a: 24,
            b: "lol".into(),
        };
        let _item_b: Result<ItemB, _> = item_a.try_to_cloned();
    }

    #[test]
    fn try_cloned_from() {
        let item_a = ItemA {
            a: 24,
            b: "lol".into(),
        };
        let _item_b = ItemB::try_cloned_from(&item_a);
    }
}