# Struct serde::de::value::MapDeserializer

source · ```
pub struct MapDeserializer<'de, I, E>{
iter: Fuse<I>,
value: Option<<I::Item as Pair>::Second>,
count: usize,
lifetime: PhantomData<&'de ()>,
error: PhantomData<E>,
}
```

## Expand description

A deserializer that iterates over a map.

## Fields§

§`iter: Fuse<I>`

§`value: Option<<I::Item as Pair>::Second>`

§`count: usize`

§`lifetime: PhantomData<&'de ()>`

§`error: PhantomData<E>`

## Implementations§

source§### impl<'de, I, E> MapDeserializer<'de, I, E>

### impl<'de, I, E> MapDeserializer<'de, I, E>

source§### impl<'de, I, E> MapDeserializer<'de, I, E>

### impl<'de, I, E> MapDeserializer<'de, I, E>

## Trait Implementations§

source§### impl<'de, I, E> Clone for MapDeserializer<'de, I, E>

### impl<'de, I, E> Clone for MapDeserializer<'de, I, E>

source§### impl<'de, I, E> Debug for MapDeserializer<'de, I, E>

### impl<'de, I, E> Debug for MapDeserializer<'de, I, E>

source§### impl<'de, I, E> Deserializer<'de> for MapDeserializer<'de, I, E>

### impl<'de, I, E> Deserializer<'de> for MapDeserializer<'de, I, E>

source§#### fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

#### fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

Require the

`Deserializer`

to figure out how to drive the visitor based
on what data type is in the input. Read moresource§#### fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

#### fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a sequence of values.source§#### fn deserialize_tuple<V>(
self,
len: usize,
visitor: V
) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

#### fn deserialize_tuple<V>(
self,
len: usize,
visitor: V
) -> Result<V::Value, Self::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a sequence of values and
knows how many values there are without looking at the serialized data.source§#### fn deserialize_bool<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_bool<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `bool`

value.source§#### fn deserialize_i8<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_i8<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an `i8`

value.source§#### fn deserialize_i16<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_i16<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an `i16`

value.source§#### fn deserialize_i32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_i32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an `i32`

value.source§#### fn deserialize_i64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_i64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an `i64`

value.source§#### fn deserialize_i128<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_i128<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

source§#### fn deserialize_u8<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_u8<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `u8`

value.source§#### fn deserialize_u16<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_u16<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `u16`

value.source§#### fn deserialize_u32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_u32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `u32`

value.source§#### fn deserialize_u64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_u64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `u64`

value.source§#### fn deserialize_u128<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_u128<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

source§#### fn deserialize_f32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_f32<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `f32`

value.source§#### fn deserialize_f64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_f64<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `f64`

value.source§#### fn deserialize_char<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_char<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a `char`

value.source§#### fn deserialize_str<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_str<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a string value and does
not benefit from taking ownership of buffered data owned by the
`Deserializer`

. Read moresource§#### fn deserialize_string<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_string<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a string value and would
benefit from taking ownership of buffered data owned by the
`Deserializer`

. Read moresource§#### fn deserialize_bytes<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_bytes<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a byte array and does not
benefit from taking ownership of buffered data owned by the
`Deserializer`

. Read moresource§#### fn deserialize_byte_buf<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_byte_buf<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a byte array and would
benefit from taking ownership of buffered data owned by the
`Deserializer`

. Read moresource§#### fn deserialize_option<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_option<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an optional value. Read moresource§#### fn deserialize_unit<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_unit<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a unit value.source§#### fn deserialize_unit_struct<V>(
self,
name: &'static str,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_unit_struct<V>(
self,
name: &'static str,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a unit struct with a
particular name.source§#### fn deserialize_newtype_struct<V>(
self,
name: &'static str,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_newtype_struct<V>(
self,
name: &'static str,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a newtype struct with a
particular name.source§#### fn deserialize_tuple_struct<V>(
self,
name: &'static str,
len: usize,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_tuple_struct<V>(
self,
name: &'static str,
len: usize,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a tuple struct with a
particular name and number of fields.source§#### fn deserialize_map<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_map<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a map of key-value pairs.source§#### fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_struct<V>(
self,
name: &'static str,
fields: &'static [&'static str],
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting a struct with a particular
name and fields.source§#### fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting an enum value with a
particular name and possible variants.source§#### fn deserialize_identifier<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_identifier<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type is expecting the name of a struct
field or the discriminant of an enum variant.source§#### fn deserialize_ignored_any<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

#### fn deserialize_ignored_any<V>(
self,
visitor: V
) -> Result<V::Value, <Self as Deserializer<'de>>::Error>where
V: Visitor<'de>,

Hint that the

`Deserialize`

type needs to deserialize a value whose type
doesn’t matter because it is ignored. Read moresource§#### fn is_human_readable(&self) -> bool

#### fn is_human_readable(&self) -> bool

Determine whether

`Deserialize`

implementations should expect to
deserialize their human-readable form. Read moresource§### impl<'de, I, E> MapAccess<'de> for MapDeserializer<'de, I, E>

### impl<'de, I, E> MapAccess<'de> for MapDeserializer<'de, I, E>

source§#### fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>where
T: DeserializeSeed<'de>,

#### 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. Read moresource§#### fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error>where
T: DeserializeSeed<'de>,

#### 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. Read moresource§#### fn next_entry_seed<TK, TV>(
&mut self,
kseed: TK,
vseed: TV
) -> Result<Option<(TK::Value, TV::Value)>, Self::Error>where
TK: DeserializeSeed<'de>,
TV: DeserializeSeed<'de>,

#### fn next_entry_seed<TK, TV>(
&mut self,
kseed: TK,
vseed: TV
) -> Result<Option<(TK::Value, TV::Value)>, Self::Error>where
TK: DeserializeSeed<'de>,
TV: 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. Read moresource§#### fn size_hint(&self) -> Option<usize>

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

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

source§#### fn next_key<K>(&mut self) -> Result<Option<K>, Self::Error>where
K: Deserialize<'de>,

#### 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. Read moresource§#### fn next_value<V>(&mut self) -> Result<V, Self::Error>where
V: Deserialize<'de>,

#### 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. Read moresource§#### fn next_entry<K, V>(&mut self) -> Result<Option<(K, V)>, Self::Error>where
K: Deserialize<'de>,
V: Deserialize<'de>,

#### 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. Read moresource§### impl<'de, I, E> SeqAccess<'de> for MapDeserializer<'de, I, E>

### impl<'de, I, E> SeqAccess<'de> for MapDeserializer<'de, I, E>

source§#### fn next_element_seed<T>(
&mut self,
seed: T
) -> Result<Option<T::Value>, Self::Error>where
T: DeserializeSeed<'de>,

#### fn next_element_seed<T>(
&mut self,
seed: T
) -> Result<Option<T::Value>, Self::Error>where
T: DeserializeSeed<'de>,

This returns

`Ok(Some(value))`

for the next value in the sequence, or
`Ok(None)`

if there are no more remaining items. Read moresource§#### fn size_hint(&self) -> Option<usize>

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

Returns the number of elements remaining in the sequence, if known.

source§#### fn next_element<T>(&mut self) -> Result<Option<T>, Self::Error>where
T: Deserialize<'de>,

#### fn next_element<T>(&mut self) -> Result<Option<T>, Self::Error>where
T: Deserialize<'de>,

This returns

`Ok(Some(value))`

for the next value in the sequence, or
`Ok(None)`

if there are no more remaining items. Read more## Auto Trait Implementations§

### impl<'de, I, E> Freeze for MapDeserializer<'de, I, E>

### impl<'de, I, E> RefUnwindSafe for MapDeserializer<'de, I, E>

### impl<'de, I, E> Send for MapDeserializer<'de, I, E>

### impl<'de, I, E> Sync for MapDeserializer<'de, I, E>

### impl<'de, I, E> Unpin for MapDeserializer<'de, I, E>

### impl<'de, I, E> UnwindSafe for MapDeserializer<'de, I, E>

## Blanket Implementations§

source§### impl<T> BorrowMut<T> for Twhere
T: ?Sized,

### impl<T> BorrowMut<T> for Twhere
T: ?Sized,

source§#### fn borrow_mut(&mut self) -> &mut T

#### fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more