diesel/expression_methods/
eq_all.rs

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1use crate::expression::grouped::Grouped;
2use crate::expression::operators::And;
3use crate::expression::Expression;
4use crate::expression_methods::*;
5use crate::sql_types::Bool;
6
7/// This method is used by `FindDsl` to work with tuples. Because we cannot
8/// express this without specialization or overlapping impls, it is brute force
9/// implemented on columns in the `column!` macro.
10#[doc(hidden)]
11pub trait EqAll<Rhs> {
12    type Output: Expression<SqlType = Bool>;
13
14    fn eq_all(self, rhs: Rhs) -> Self::Output;
15}
16
17macro_rules! impl_eq_all {
18    // General case for 2+ elements
19    (
20        ($Left1:ident, $($Left:ident,)+)
21        ($Right1:ident, $($Right:ident,)+)
22    ) => {
23        #[allow(non_snake_case)]
24        impl<$Left1, $($Left,)+ $Right1, $($Right,)+>
25            EqAll<($Right1, $($Right,)+)> for ($Left1, $($Left,)+)
26        where
27            $Left1: EqAll<$Right1>,
28            ($($Left,)+): EqAll<($($Right,)+)>,
29        {
30            type Output = Grouped<And<
31                <$Left1 as EqAll<$Right1>>::Output,
32                <($($Left,)+) as EqAll<($($Right,)+)>>::Output,
33            >>;
34
35            fn eq_all(self, rhs: ($Right1, $($Right,)+)) -> Self::Output {
36                let ($Left1, $($Left,)+) = self;
37                let ($Right1, $($Right,)+) = rhs;
38                $Left1.eq_all($Right1).and(($($Left,)+).eq_all(($($Right,)+)))
39            }
40        }
41    };
42
43    // Special case for 1 element
44    (
45        ($Left:ident,) ($Right:ident,)
46    ) => {
47        impl<$Left, $Right> EqAll<($Right,)> for ($Left,)
48        where
49            $Left: EqAll<$Right>,
50        {
51            type Output = <$Left as EqAll<$Right>>::Output;
52
53            fn eq_all(self, rhs: ($Right,)) -> Self::Output {
54                self.0.eq_all(rhs.0)
55            }
56        }
57    };
58}
59
60macro_rules! impl_eq_all_for_all_tuples {
61    ($(
62        $unused1:tt {
63            $($unused2:tt -> $Left:ident, $Right:ident, $unused3:tt,)+
64        }
65    )+) => {
66        $(
67            impl_eq_all!(($($Left,)+) ($($Right,)+));
68        )+
69    };
70}
71
72diesel_derives::__diesel_for_each_tuple!(impl_eq_all_for_all_tuples);
diesel/expression_methods/eq_all.rs

diesel/expression_methods/
eq_all.rs
