Trait parity_scale_codec::EncodeAppend

pub trait EncodeAppend {
    type Item: Encode;

    fn append_or_new<EncodeLikeItem, I>(
        self_encoded: Vec<u8>,
        iter: I
    ) -> Result<Vec<u8>, Error>
    where
        I: IntoIterator<Item = EncodeLikeItem>,
        EncodeLikeItem: EncodeLike<Self::Item>,
        I::IntoIter: ExactSizeIterator;
}

Trait that allows to append items to an encoded representation without decoding all previous added items.

Required Associated Types

type Item: Encode

The item that will be appended.

Required Methods

fn append_or_new<EncodeLikeItem, I>(
    self_encoded: Vec<u8>,
    iter: I
) -> Result<Vec<u8>, Error>where
    I: IntoIterator<Item = EncodeLikeItem>,
    EncodeLikeItem: EncodeLike<Self::Item>,
    I::IntoIter: ExactSizeIterator,

Append all items in iter to the given self_encoded representation or if self_encoded value is empty, iter is encoded to the Self representation.

Example

// Some encoded data
let data = Vec::new();

let item = 8u32;
let encoded = <Vec<u32> as EncodeAppend>::append_or_new(data, std::iter::once(&item)).expect("Adds new element");

// Add multiple element
<Vec<u32> as EncodeAppend>::append_or_new(encoded, &[700u32, 800u32, 10u32]).expect("Adds new elements");

Implementations on Foreign Types

impl<T: Encode> EncodeAppend for Vec<T>

type Item = T

fn append_or_new<EncodeLikeItem, I>(
    self_encoded: Vec<u8>,
    iter: I
) -> Result<Vec<u8>, Error>where
    I: IntoIterator<Item = EncodeLikeItem>,
    EncodeLikeItem: EncodeLike<Self::Item>,
    I::IntoIter: ExactSizeIterator,

impl<T: Encode> EncodeAppend for VecDeque<T>

type Item = T

fn append_or_new<EncodeLikeItem, I>(
    self_encoded: Vec<u8>,
    iter: I
) -> Result<Vec<u8>, Error>where
    I: IntoIterator<Item = EncodeLikeItem>,
    EncodeLikeItem: EncodeLike<Self::Item>,
    I::IntoIter: ExactSizeIterator,

Implementors