diesel/expression/
helper_types.rs

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
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
//! The types in this module are all shorthand for `PredicateType<Lhs,
//! AsExpr<Rhs, Lhs>>`. Since we often need to return concrete types, instead of
//! a boxed trait object, these can be useful for writing concise return types.
use super::array_comparison::{AsInExpression, In, NotIn};
use super::grouped::Grouped;
use super::select_by::SelectBy;
use super::{AsExpression, Expression};
use crate::expression;
use crate::expression_methods::PreferredBoolSqlType;
use crate::sql_types;

/// The SQL type of an expression
pub type SqlTypeOf<Expr> = <Expr as Expression>::SqlType;

/// The type of `Item` when converted to an expression with the same type as `TargetExpr`
pub type AsExpr<Item, TargetExpr> = AsExprOf<Item, SqlTypeOf<TargetExpr>>;

/// The type of `Item` when converted to an expression of `Type`
pub type AsExprOf<Item, Type> = <Item as AsExpression<Type>>::Expression;

/// The return type of
/// [`lhs.eq(rhs)`](crate::expression_methods::ExpressionMethods::eq())
pub type Eq<Lhs, Rhs> = Grouped<super::operators::Eq<Lhs, AsExpr<Rhs, Lhs>>>;

/// The return type of
/// [`lhs.ne(rhs)`](crate::expression_methods::ExpressionMethods::ne())
pub type NotEq<Lhs, Rhs> = Grouped<super::operators::NotEq<Lhs, AsExpr<Rhs, Lhs>>>;

#[doc(hidden)] // required for `#[auto_type]`
pub type Ne<Lhs, Rhs> = NotEq<Lhs, Rhs>;

/// The return type of
/// [`lhs.eq_any(rhs)`](crate::expression_methods::ExpressionMethods::eq_any())
pub type EqAny<Lhs, Rhs> = Grouped<In<Lhs, <Rhs as AsInExpression<SqlTypeOf<Lhs>>>::InExpression>>;

/// The return type of
/// [`lhs.ne_all(rhs)`](crate::expression_methods::ExpressionMethods::ne_all())
pub type NeAny<Lhs, Rhs> =
    Grouped<NotIn<Lhs, <Rhs as AsInExpression<SqlTypeOf<Lhs>>>::InExpression>>;

#[doc(hidden)] // required for `#[auto_type]`
pub type NeAll<Lhs, Rhs> = NeAny<Lhs, Rhs>;

/// The return type of
/// [`expr.is_null()`](crate::expression_methods::ExpressionMethods::is_null())
pub type IsNull<Expr> = Grouped<super::operators::IsNull<Expr>>;

/// The return type of
/// [`expr.is_not_null()`](crate::expression_methods::ExpressionMethods::is_not_null())
pub type IsNotNull<Expr> = Grouped<super::operators::IsNotNull<Expr>>;

/// The return type of
/// [`lhs.gt(rhs)`](crate::expression_methods::ExpressionMethods::gt())
pub type Gt<Lhs, Rhs> = Grouped<super::operators::Gt<Lhs, AsExpr<Rhs, Lhs>>>;

/// The return type of
/// [`lhs.ge(rhs)`](crate::expression_methods::ExpressionMethods::ge())
pub type GtEq<Lhs, Rhs> = Grouped<super::operators::GtEq<Lhs, AsExpr<Rhs, Lhs>>>;

#[doc(hidden)] // required for `#[auto_type]`
pub type Ge<Lhs, Rhs> = GtEq<Lhs, Rhs>;

/// The return type of
/// [`lhs.lt(rhs)`](crate::expression_methods::ExpressionMethods::lt())
pub type Lt<Lhs, Rhs> = Grouped<super::operators::Lt<Lhs, AsExpr<Rhs, Lhs>>>;

/// The return type of
/// [`lhs.le(rhs)`](crate::expression_methods::ExpressionMethods::le())
pub type LtEq<Lhs, Rhs> = Grouped<super::operators::LtEq<Lhs, AsExpr<Rhs, Lhs>>>;

#[doc(hidden)] // required for `#[auto_type]`
pub type Le<Lhs, Rhs> = LtEq<Lhs, Rhs>;

/// The return type of
/// [`lhs.between(lower, upper)`](crate::expression_methods::ExpressionMethods::between())
pub type Between<Lhs, Lower, Upper> = Grouped<
    super::operators::Between<Lhs, super::operators::And<AsExpr<Lower, Lhs>, AsExpr<Upper, Lhs>>>,
>;

/// The return type of
/// [`lhs.not_between(lower, upper)`](crate::expression_methods::ExpressionMethods::not_between())
pub type NotBetween<Lhs, Lower, Upper> = Grouped<
    super::operators::NotBetween<
        Lhs,
        super::operators::And<AsExpr<Lower, Lhs>, AsExpr<Upper, Lhs>>,
    >,
>;

/// The return type of
/// [`lhs.concat(rhs)`](crate::expression_methods::TextExpressionMethods::concat())
pub type Concat<Lhs, Rhs> = Grouped<super::operators::Concat<Lhs, AsExpr<Rhs, Lhs>>>;

/// The return type of
/// [`expr.desc()`](crate::expression_methods::ExpressionMethods::desc())
pub type Desc<Expr> = super::operators::Desc<Expr>;

/// The return type of
/// [`expr.asc()`](crate::expression_methods::ExpressionMethods::asc())
pub type Asc<Expr> = super::operators::Asc<Expr>;

/// The return type of
/// [`expr.nullable()`](crate::expression_methods::NullableExpressionMethods::nullable())
pub type Nullable<Expr> = super::nullable::Nullable<Expr>;

/// The return type of
/// [`expr.assume_not_null()`](crate::expression_methods::NullableExpressionMethods::assume_not_null())
pub type AssumeNotNull<Expr> = super::assume_not_null::AssumeNotNull<Expr>;

/// The return type of
/// [`lhs.and(rhs)`](crate::expression_methods::BoolExpressionMethods::and())
pub type And<Lhs, Rhs, ST = <Rhs as PreferredBoolSqlType>::PreferredSqlType> =
    Grouped<super::operators::And<Lhs, AsExprOf<Rhs, ST>>>;

/// The return type of
/// [`lhs.or(rhs)`](crate::expression_methods::BoolExpressionMethods::or())
pub type Or<Lhs, Rhs, ST = <Rhs as PreferredBoolSqlType>::PreferredSqlType> =
    Grouped<super::operators::Or<Lhs, AsExprOf<Rhs, ST>>>;

/// The return type of
/// [`lhs.escape('x')`](crate::expression_methods::EscapeExpressionMethods::escape())
pub type Escape<Lhs> = Grouped<
    super::operators::Escape<
        <Lhs as crate::expression_methods::EscapeExpressionMethods>::TextExpression,
        AsExprOf<String, sql_types::VarChar>,
    >,
>;

/// The return type of
/// [`lhs.like(rhs)`](crate::expression_methods::TextExpressionMethods::like())
pub type Like<Lhs, Rhs> = Grouped<super::operators::Like<Lhs, AsExprOf<Rhs, SqlTypeOf<Lhs>>>>;

/// The return type of
/// [`lhs.not_like(rhs)`](crate::expression_methods::TextExpressionMethods::not_like())
pub type NotLike<Lhs, Rhs> = Grouped<super::operators::NotLike<Lhs, AsExprOf<Rhs, SqlTypeOf<Lhs>>>>;

/// The return type of [`case_when()`](expression::case_when::case_when)
#[allow(non_camel_case_types)] // required for `#[auto_type]`
pub type case_when<C, T, ST = <T as Expression>::SqlType> = expression::case_when::CaseWhen<
    expression::case_when::CaseWhenConditionsLeaf<Grouped<C>, Grouped<AsExprOf<T, ST>>>,
    expression::case_when::NoElseExpression,
>;
/// The return type of [`case_when(...).when(...)`](expression::CaseWhen::when)
pub type When<W, C, T> = expression::case_when::CaseWhen<
    expression::case_when::CaseWhenConditionsIntermediateNode<
        Grouped<C>,
        Grouped<AsExprOf<T, <W as expression::case_when::CaseWhenTypesExtractor>::OutputExpressionSpecifiedSqlType>>,
        <W as expression::case_when::CaseWhenTypesExtractor>::Whens,
    >,
    <W as expression::case_when::CaseWhenTypesExtractor>::Else,
>;
/// The return type of [`case_when(...).otherwise(...)`](expression::case_when::CaseWhen::otherwise)
pub type Otherwise<W, E> = expression::case_when::CaseWhen<
    <W as expression::case_when::CaseWhenTypesExtractor>::Whens,
    expression::case_when::ElseExpression<Grouped<AsExprOf<E, <W as expression::case_when::CaseWhenTypesExtractor>::OutputExpressionSpecifiedSqlType>>>,
>;

/// Represents the return type of [`.as_select()`](crate::prelude::SelectableHelper::as_select)
pub type AsSelect<Source, DB> = SelectBy<Source, DB>;

/// Represents the return type of [`.into_sql()`](crate::expression::IntoSql::into_sql)
pub type IntoSql<Item, SqlType> = AsExprOf<Item, SqlType>;

/// The return type of [`alias.field(field)`](crate::query_source::Alias::field)
pub type Field<Alias, Field> = Fields<Alias, Field>;

/// The return type of [`alias.fields(fields)`](crate::query_source::Alias::fields)
pub type Fields<Alias, Fields> = <Fields as crate::query_source::aliasing::FieldAliasMapper<
    <Alias as crate::query_source::aliasing::GetAliasSourceFromAlias>::Source,
>>::Out;

// we allow unreachable_pub here
// as rustc otherwise shows false positives
// for every item in this module. We reexport
// everything from `crate::helper_types::`
#[doc(inline)]
#[allow(unreachable_pub)]
pub use super::functions::helper_types::*;

#[doc(inline)]
#[cfg(feature = "postgres_backend")]
#[allow(unreachable_pub)]
pub use crate::pg::expression::helper_types::*;

#[doc(inline)]
#[cfg(feature = "sqlite")]
#[allow(unreachable_pub)]
pub use crate::sqlite::expression::helper_types::*;