[−]Trait astral::thirdparty::serde::de::Expected
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 be a noun or noun phrase that completes 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.
ⓘThis code runs with edition 2018
fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> where E: de::Error, { Err(de::Error::invalid_type(Unexpected::Bool(v), &self)) }
Outside of a Visitor
, &"..."
can be used.
ⓘThis code runs with edition 2018
return Err(de::Error::invalid_type(Unexpected::Bool(v), &"a negative integer"));
Required methods
fn fmt(&self, formatter: &mut Formatter) -> Result<(), Error>
Format an explanation of what data was being expected. Same signature as
the Display
and Debug
traits.