diesel/macros/
query_id.rs

1/// Provides a standard implementation of `QueryId`.
2/// Apps should not need to concern themselves with this macro.
3///
4/// This macro should be called with the name of your type, along with all of
5/// it's type parameters.
6/// If the SQL generated by your type not uniquely identifiable by the type
7/// itself, you should put `noop:` in front.
8///
9/// For example, given the type `And<Left, Right>`, invoking
10/// `impl_query_id!(And<Left, Right>)` will generate:
11///
12/// ```rust,ignore
13/// impl<Left, Right> QueryId for And<Left, Right>
14/// where
15///     Left: QueryId,
16///     Right: QueryId,
17/// {
18///     type QueryId = And<Left::QueryId, Right::QueryId>;
19///
20///     const HAS_STATIC_QUERY_ID: bool = Left::HAS_STATIC_QUERY_ID && Right::HAS_STATIC_QUERY_ID;
21/// }
22/// ```
23///
24/// Invoking `impl_query_id!(noop: And<Left, Right>)` will generate:
25///
26/// ```rust,ignore
27/// impl<Left, Right> QueryId for And<Left, Right> {
28///     type QueryId = ();
29///
30///     const HAS_STATIC_QUERY_ID: bool = false;
31/// }
32/// ```
33#[macro_export]
34#[cfg(feature = "with-deprecated")]
35#[deprecated(since = "1.1.0", note = "Use `#[derive(QueryId)]` instead")]
36macro_rules! impl_query_id {
37    ($name: ident) => {
38        impl $crate::query_builder::QueryId for $name {
39            type QueryId = Self;
40
41            const HAS_STATIC_QUERY_ID: bool = true;
42        }
43    };
44
45    ($name: ident<$($ty_param: ident),+>) => {
46        #[allow(non_camel_case_types)]
47        impl<$($ty_param),*> $crate::query_builder::QueryId for $name<$($ty_param),*> where
48            $($ty_param: $crate::query_builder::QueryId),*
49        {
50            type QueryId = $name<$($ty_param::QueryId),*>;
51
52            const HAS_STATIC_QUERY_ID: bool = $($ty_param::HAS_STATIC_QUERY_ID &&)* true;
53        }
54    };
55
56    (noop: $name: ident) => {
57        impl $crate::query_builder::QueryId for $name {
58            type QueryId = ();
59
60            const HAS_STATIC_QUERY_ID: bool = false;
61        }
62    };
63
64    (noop: $name: ident<$($ty_param: ident),+>) => {
65        #[allow(non_camel_case_types)]
66        impl<$($ty_param),*> $crate::query_builder::QueryId for $name<$($ty_param),*> {
67            type QueryId = ();
68
69            const HAS_STATIC_QUERY_ID: bool = false;
70        }
71    }
72}
diesel/macros/query_id.rs

diesel/macros/
query_id.rs
