Trait diesel::expression::BoxableExpression
[−]
[src]
pub trait BoxableExpression<QS, ST: NativeSqlType>: Expression + SelectableExpression<QS, ST> + NonAggregate { }
Helper trait used when boxing expressions. This exists to work around the
fact that Rust will not let us use non-core types as bounds on a trait
object (you could not return Box<Expression+NonAggregate>
)
Implementors
impl<QS, T, ST> BoxableExpression<QS, ST> for T where ST: NativeSqlType, T: Expression + SelectableExpression<QS, ST> + NonAggregate