Trait diesel::expression::BoxableExpression [] [src]

pub trait BoxableExpression<QS, DB> where DB: Backend,
               Self: Expression,
               Self: SelectableExpression<QS>,
               Self: NonAggregate,
               Self: QueryFragment<DB>
{ }

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>)

Trait Implementations

impl<QS, ST, STS, DB> QueryId for BoxableExpression<QS, DB, SqlType=ST, SqlTypeForSelect=STS>
[src]

Implementors