# Trait serde::de::SeqAccess

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    pub trait SeqAccess<'de> {
        type Error: Error;

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

        fn next_element<T>(&mut self) -> Result<Option<T>, Self::Error>
        where
            T: Deserialize<'de>,
        { ... }
        fn size_hint(&self) -> Option<usize> { ... }
    }

Expand description

Provides a `Visitor` access to each element of a sequence in the input.

This is a trait that a `Deserializer` passes to a `Visitor` implementation, which deserializes each item in a sequence.

## Lifetime

The `'de` lifetime of this trait is the lifetime of data that may be borrowed by deserialized sequence elements. See the page Understanding deserializer lifetimes for a more detailed explanation of these lifetimes.

## Example implementation

The example data format presented on the website demonstrates an implementation of `SeqAccess` for a basic JSON data format.

## Required Associated Types

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#### type Error: Error

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

## Required Methods

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#### 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.

`Deserialize` implementations should typically use `SeqAccess::next_element` instead.

## Provided Methods

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#### 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.

This method exists as a convenience for `Deserialize` implementations. `SeqAccess` implementations should not override the default behavior.

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

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

## Implementations on Foreign Types

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### impl<'de, 'a, A: ?Sized> SeqAccess<'de> for &'a mut A where
A: SeqAccess<'de>,

#### type Error = <A as SeqAccess<'de>>::Error

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

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

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

## Implementors

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### impl<'de, I, E> SeqAccess<'de> for MapDeserializer<'de, I, E> where
I: Iterator,
I::Item: Pair,
<I::Item as Pair>::First: IntoDeserializer<'de, E>,
<I::Item as Pair>::Second: IntoDeserializer<'de, E>,
E: Error,

#### type Error = E

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### impl<'de, I, T, E> SeqAccess<'de> for SeqDeserializer<I, E> where
I: Iterator<Item = T>,
T: IntoDeserializer<'de, E>,
E: Error,

#### type Error = E