Trait serde::de::Expected
[−]
[src]
pub trait Expected { fn fmt(&self, formatter: &mut Formatter) -> Result; }
Expected
represents an explanation of what data a Visitor
was expecting
to receive.
This is used as an argument to the invalid_type
, invalid_value
, and
invalid_length
methods of the Error
trait to build error messages. The
message should complete the sentence "This Visitor expects to receive ...",
for example the message could be "an integer between 0 and 64". The message
should not be capitalized and should not end with a period.
Within the context of a Visitor
implementation, the Visitor
itself
(&self
) is an implementation of this trait.
fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> where E: Error { Err(Error::invalid_type(Unexpected::Bool(v), &self)) }
Outside of a Visitor
, &"..."
can be used.
return Err(Error::invalid_type(Unexpected::Bool(v), &"a negative integer"));
Required Methods
fn fmt(&self, formatter: &mut Formatter) -> Result
Format an explanation of what data was being expected. Same signature as
the Display
and Debug
traits.