diesel/expression/
helper_types.rs

1//! The types in this module are all shorthand for `PredicateType<Lhs,
2//! AsExpr<Rhs, Lhs>>`. Since we often need to return concrete types, instead of
3//! a boxed trait object, these can be useful for writing concise return types.
4use super::array_comparison::{AsInExpression, In, NotIn};
5use super::grouped::Grouped;
6use super::{AsExpression, Expression};
7use sql_types;
8
9/// The SQL type of an expression
10pub type SqlTypeOf<Expr> = <Expr as Expression>::SqlType;
11
12/// The type of `Item` when converted to an expression with the same type as `TargetExpr`
13pub type AsExpr<Item, TargetExpr> = AsExprOf<Item, SqlTypeOf<TargetExpr>>;
14
15/// The type of `Item` when converted to an expression of `Type`
16pub type AsExprOf<Item, Type> = <Item as AsExpression<Type>>::Expression;
17
18/// The return type of
19/// [`lhs.eq(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.eq)
20pub type Eq<Lhs, Rhs> = super::operators::Eq<Lhs, AsExpr<Rhs, Lhs>>;
21
22/// The return type of
23/// [`lhs.ne(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.ne)
24pub type NotEq<Lhs, Rhs> = super::operators::NotEq<Lhs, AsExpr<Rhs, Lhs>>;
25
26/// The return type of
27/// [`lhs.eq_any(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.eq_any)
28pub type EqAny<Lhs, Rhs> = In<Lhs, <Rhs as AsInExpression<SqlTypeOf<Lhs>>>::InExpression>;
29
30/// The return type of
31/// [`lhs.ne_any(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.ne_any)
32pub type NeAny<Lhs, Rhs> = NotIn<Lhs, <Rhs as AsInExpression<SqlTypeOf<Lhs>>>::InExpression>;
33
34/// The return type of
35/// [`expr.is_null()`](../expression_methods/trait.ExpressionMethods.html#method.is_null)
36pub type IsNull<Expr> = super::operators::IsNull<Expr>;
37
38/// The return type of
39/// [`expr.is_not_null()`](../expression_methods/trait.ExpressionMethods.html#method.is_not_null)
40pub type IsNotNull<Expr> = super::operators::IsNotNull<Expr>;
41
42/// The return type of
43/// [`lhs.gt(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.gt)
44pub type Gt<Lhs, Rhs> = super::operators::Gt<Lhs, AsExpr<Rhs, Lhs>>;
45
46/// The return type of
47/// [`lhs.ge(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.ge)
48pub type GtEq<Lhs, Rhs> = super::operators::GtEq<Lhs, AsExpr<Rhs, Lhs>>;
49
50/// The return type of
51/// [`lhs.lt(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.lt)
52pub type Lt<Lhs, Rhs> = super::operators::Lt<Lhs, AsExpr<Rhs, Lhs>>;
53
54/// The return type of
55/// [`lhs.le(rhs)`](../expression_methods/trait.ExpressionMethods.html#method.le)
56pub type LtEq<Lhs, Rhs> = super::operators::LtEq<Lhs, AsExpr<Rhs, Lhs>>;
57
58/// The return type of
59/// [`lhs.between(lower, upper)`](../expression_methods/trait.ExpressionMethods.html#method.between)
60pub type Between<Lhs, Lower, Upper> =
61    super::operators::Between<Lhs, super::operators::And<AsExpr<Lower, Lhs>, AsExpr<Upper, Lhs>>>;
62
63/// The return type of
64/// [`lhs.not_between(lower, upper)`](../expression_methods/trait.ExpressionMethods.html#method.not_between)
65pub type NotBetween<Lhs, Lower, Upper> = super::operators::NotBetween<
66    Lhs,
67    super::operators::And<AsExpr<Lower, Lhs>, AsExpr<Upper, Lhs>>,
68>;
69
70/// The return type of
71/// [`expr.desc()`](../expression_methods/trait.ExpressionMethods.html#method.desc)
72pub type Desc<Expr> = super::operators::Desc<Expr>;
73
74/// The return type of
75/// [`expr.asc()`](../expression_methods/trait.ExpressionMethods.html#method.asc)
76pub type Asc<Expr> = super::operators::Asc<Expr>;
77
78/// The return type of
79/// [`expr.nullable()`](../expression_methods/trait.NullableExpressionMethods.html#method.nullable)
80pub type Nullable<Expr> = super::nullable::Nullable<Expr>;
81
82/// The return type of
83/// [`lhs.and(rhs)`](../expression_methods/trait.BoolExpressionMethods.html#method.and)
84pub type And<Lhs, Rhs> = super::operators::And<Lhs, AsExprOf<Rhs, sql_types::Bool>>;
85
86/// The return type of
87/// [`lhs.or(rhs)`](../expression_methods/trait.BoolExpressionMethods.html#method.or)
88pub type Or<Lhs, Rhs> = Grouped<super::operators::Or<Lhs, AsExprOf<Rhs, sql_types::Bool>>>;
89
90/// The return type of
91/// [`lhs.escape('x')`](../expression_methods/trait.EscapeExpressionMethods.html#method.escape)
92pub type Escape<Lhs> = super::operators::Escape<Lhs, AsExprOf<String, sql_types::VarChar>>;
93
94/// The return type of
95/// [`lhs.like(rhs)`](../expression_methods/trait.TextExpressionMethods.html#method.like)
96pub type Like<Lhs, Rhs> = super::operators::Like<Lhs, AsExprOf<Rhs, sql_types::VarChar>>;
97
98/// The return type of
99/// [`lhs.not_like(rhs)`](../expression_methods/trait.TextExpressionMethods.html#method.not_like)
100pub type NotLike<Lhs, Rhs> = super::operators::NotLike<Lhs, AsExprOf<Rhs, sql_types::VarChar>>;
101
102#[doc(inline)]
103pub use super::functions::helper_types::*;
diesel/expression/helper_types.rs

diesel/expression/
helper_types.rs
