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// build-pass
//
// Tests that overflows do not occur in certain situations
// related to generic diesel code
use mini_diesel::*;
pub trait HandleDelete<K> {}
pub fn handle_delete<D, R>()
where
R: HasTable,
R::Table: HandleDelete<D> + 'static,
{
}
impl<K, T> HandleDelete<K> for T
where
T: Table + HasTable<Table = T> + 'static,
K: 'static,
&'static K: Identifiable<Table = T>,
T::PrimaryKey: EqAll<<&'static K as Identifiable>::Id>,
T::Query: FilterDsl<<T::PrimaryKey as EqAll<<&'static K as Identifiable>::Id>>::Output>,
Filter<T::Query, <T::PrimaryKey as EqAll<<&'static K as Identifiable>::Id>>::Output>:
IntoUpdateTarget<Table = T>,
{
}
mod mini_diesel {
pub trait HasTable {
type Table: Table;
}
pub trait Identifiable: HasTable {
type Id;
}
pub trait EqAll<Rhs> {
type Output;
}
pub trait IntoUpdateTarget: HasTable {
type WhereClause;
}
pub trait Query {
type SqlType;
}
pub trait AsQuery {
type Query: Query;
}
impl<T: Query> AsQuery for T {
type Query = Self;
}
pub trait FilterDsl<Predicate> {
type Output;
}
impl<T, Predicate> FilterDsl<Predicate> for T
where
T: Table,
T::Query: FilterDsl<Predicate>,
{
type Output = Filter<T::Query, Predicate>;
}
pub trait QuerySource {
type FromClause;
}
pub trait Table: QuerySource + AsQuery + Sized {
type PrimaryKey;
}
pub type Filter<Source, Predicate> = <Source as FilterDsl<Predicate>>::Output;
}
fn main() {}
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