[−][src]Module diesel::helper_types

Provide helper types for concisely writing the return type of functions. As with iterators, it is unfortunately difficult to return a partially constructed query without exposing the exact implementation of the function. Without higher kinded types, these various DSLs can't be combined into a single trait for boxing purposes.

All types here are in the form <FirstType as DslName<OtherTypes>>::Output. So the return type of users.filter(first_name.eq("John")).order(last_name.asc()).limit(10) would be Limit<Order<FindBy<users, first_name, &str>, Asc<last_name>>>

Type Definitions

And	The return type of `lhs.and(rhs)`
AsExpr	The type of `Item` when converted to an expression with the same type as `TargetExpr`
AsExprOf	The type of `Item` when converted to an expression of `Type`
Asc	The return type of `expr.asc()`
Between	The return type of `lhs.between(lower, upper)`
Desc	The return type of `expr.desc()`
Distinct	Represents the return type of `.distinct()`
Eq	The return type of `lhs.eq(rhs)`
EqAny	The return type of `lhs.eq_any(rhs)`
Escape	The return type of `lhs.escape('x')`
Filter	Represents the return type of `.filter(predicate)`
Find	Represents the return type of `.find(pk)`
FindBy	Represents the return type of `.filter(lhs.eq(rhs))`
ForKeyShare	Represents the return type of `.for_key_share()`
ForNoKeyUpdate	Represents the return type of `.for_no_key_update()`
ForShare	Represents the return type of `.for_share()`
ForUpdate	Represents the return type of `.for_update()`
Gt	The return type of `lhs.gt(rhs)`
GtEq	The return type of `lhs.ge(rhs)`
InnerJoin	Represents the return type of `.inner_join(rhs)`
IntoBoxed	Represents the return type of `.into_boxed::<'a, DB>()`
IsNotNull	The return type of `expr.is_not_null()`
IsNull	The return type of `expr.is_null()`
LeftJoin	Represents the return type of `.left_join(rhs)`
Like	The return type of `lhs.like(rhs)`
Limit	Represents the return type of `.limit()`
Lt	The return type of `lhs.lt(rhs)`
LtEq	The return type of `lhs.le(rhs)`
NeAny	The return type of `lhs.ne_any(rhs)`
NoWait	Represents the return type of `.no_wait()`
Not	Deprecated The return type of `not(expr)`
NotBetween	The return type of `lhs.not_between(lower, upper)`
NotEq	The return type of `lhs.ne(rhs)`
NotLike	The return type of `lhs.not_like(rhs)`
Nullable	The return type of `expr.nullable()`
NullableSelect	Represents the return type of `.nullable()`
Offset	Represents the return type of `.offset()`
Or	The return type of `lhs.or(rhs)`
OrFilter	Represents the return type of `.or_filter(predicate)`
Order	Represents the return type of `.order(ordering)`
Select	Represents the return type of `.select(selection)`
SingleValue	Represents the return type of `.single_value()`
SkipLocked	Represents the return type of `.skip_locked()`
SqlTypeOf	The SQL type of an expression
ThenOrderBy	Represents the return type of `.then_order_by(ordering)`
Update	Represents the return type of `update(lhs).set(rhs)`
avg	The return type of `avg(expr)`
max	The return type of `max(expr)`
min	The return type of `min(expr)`
not	The return type of `not(expr)`
sum	The return type of `sum(expr)`