Trait diesel:: expression:: AsExpression
[−]
[src]
pub trait AsExpression<T> { type Expression: Expression<SqlType=T>; fn as_expression(self) -> Self::Expression; }
Describes how a type can be represented as an expression for a given type.
These types couldn't just implement Expression
directly, as many things can be used as an expression of multiple types.
(String
for example, can be used as either
VarChar
or
Text
).
This trait allows us to use primitives on the right hand side of various
expressions. For example name.eq("Sean")