Struct DefaultMapAccess 

pub struct DefaultMapAccess;

A default map access that always returns None (empty map).

Implementations

impl DefaultMapAccess

pub fn new() -> Self

Creates a new default map access.

Trait Implementations

impl Default for DefaultMapAccess

fn default() -> Self

Returns the “default value” for a type.

impl<'de> MapAccess<'de> for DefaultMapAccess

type Error = Error

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

fn next_key_seed<T>( &mut self, _seed: T, ) -> Result<Option<T::Value>, Self::Error>

where T: DeserializeSeed<'de>,

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

fn next_value_seed<T>(&mut self, _seed: T) -> Result<T::Value, Self::Error>

where T: DeserializeSeed<'de>,

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

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

Returns the number of entries remaining in the map, if known.

fn next_entry_seed<K, V>( &mut self, kseed: K, vseed: V, ) -> Result<Option<(<K as DeserializeSeed<'de>>::Value, <V as DeserializeSeed<'de>>::Value)>, Self::Error>

where K: DeserializeSeed<'de>, V: DeserializeSeed<'de>,

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

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

where K: Deserialize<'de>,

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

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

where V: Deserialize<'de>,

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

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

where K: Deserialize<'de>, V: Deserialize<'de>,

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