blob: 3e68b1401020f205f712fb7b5fd61866547a4c73 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
|
// Regression test for #80953. Hitting the recursion limit in projection
// is non-fatal. The above code, minimised from wundergraph shows a case
// where this is relied on.
// check-pass
struct AlternateTable {}
struct AlternateQuery {}
pub trait Query {}
pub trait AsQuery {
type Query;
}
impl<T: Query> AsQuery for T {
type Query = Self;
}
impl AsQuery for AlternateTable {
type Query = AlternateQuery;
}
pub trait Table: AsQuery {
type PrimaryKey;
}
impl Table for AlternateTable {
type PrimaryKey = ();
}
pub trait FilterDsl<Predicate> {
type Output;
}
pub type Filter<Source, Predicate> = <Source as FilterDsl<Predicate>>::Output;
impl<T, Predicate> FilterDsl<Predicate> for T
where
T: Table,
T::Query: FilterDsl<Predicate>,
{
type Output = Filter<T::Query, Predicate>;
}
impl<Predicate> FilterDsl<Predicate> for AlternateQuery {
type Output = &'static str;
}
pub trait HandleDelete {
type Filter;
}
impl<T> HandleDelete for T
where
T: Table,
T::Query: FilterDsl<T::PrimaryKey>,
Filter<T::Query, T::PrimaryKey>: ,
{
type Filter = Filter<T::Query, T::PrimaryKey>;
}
fn main() {
let x: <AlternateTable as HandleDelete>::Filter = "Hello, world";
println!("{}", x);
}
|
