Trait MapVisitor 

pub trait MapVisitor {
    type Error: Error;

    // Required methods
    fn visit_key<K>(&mut self) -> Result<Option<K>, Self::Error>
       where K: Deserialize;
    fn visit_value<V>(&mut self) -> Result<V, Self::Error>
       where V: Deserialize;
    fn end(&mut self) -> Result<(), Self::Error>;

    // Provided methods
    fn visit<K, V>(&mut self) -> Result<Option<(K, V)>, Self::Error>
       where K: Deserialize,
             V: Deserialize { ... }
    fn size_hint(&self) -> (usize, Option<usize>) { ... }
    fn missing_field<V>(
        &mut self,
        field: &'static str,
    ) -> Result<V, Self::Error>
       where V: Deserialize { ... }
}

MapVisitor visits each item in a sequence.

This is a trait that a Deserializer passes to a Visitor implementation.

Required Associated Types

type Error: Error

The error type that can be returned if some error occurs during deserialization.

Required Methods

fn visit_key<K>(&mut self) -> Result<Option<K>, Self::Error>

where K: Deserialize,

This returns a Ok(Some(key)) for the next key in the map, or Ok(None) if there are no more remaining items.

fn visit_value<V>(&mut self) -> Result<V, Self::Error>

where V: Deserialize,

This returns a Ok(value) for the next value in the map.

fn end(&mut self) -> Result<(), Self::Error>

This signals to the MapVisitor that the Visitor does not expect any more items.

Provided Methods

fn visit<K, V>(&mut self) -> Result<Option<(K, V)>, Self::Error>

where K: Deserialize, V: Deserialize,

This returns a Ok(Some((key, value))) for the next (key-value) pair in the map, or Ok(None) if there are no more remaining items.

fn size_hint(&self) -> (usize, Option<usize>)

Return the lower and upper bound of items remaining in the sequence.

fn missing_field<V>(&mut self, field: &'static str) -> Result<V, Self::Error>

where V: Deserialize,

Report that there

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<'a, V_> MapVisitor for &'a mut V_

where V_: MapVisitor,

type Error = <V_ as MapVisitor>::Error

fn visit<K, V>(&mut self) -> Result<Option<(K, V)>, <V_ as MapVisitor>::Error>

where K: Deserialize, V: Deserialize,

fn visit_key<K>(&mut self) -> Result<Option<K>, <V_ as MapVisitor>::Error>

where K: Deserialize,

fn visit_value<V>(&mut self) -> Result<V, <V_ as MapVisitor>::Error>

where V: Deserialize,

fn end(&mut self) -> Result<(), <V_ as MapVisitor>::Error>

fn size_hint(&self) -> (usize, Option<usize>)

Implementors

impl<I, K, V> MapVisitor for MapDeserializer<I, K, V>

where I: Iterator<Item = (K, V)>, K: ValueDeserializer, V: ValueDeserializer,

type Error = Error