parity_scale_codec/
keyedvec.rs

1// Copyright 2017, 2018 Parity Technologies
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15//! Serializer and prepender.
16
17use core::iter::Extend;
18
19use crate::{alloc::vec::Vec, codec::Codec};
20
21/// Trait to allow itself to be serialised and prepended by a given slice.
22pub trait KeyedVec {
23	/// Return an encoding of `Self` prepended by given slice.
24	fn to_keyed_vec(&self, prepend_key: &[u8]) -> Vec<u8>;
25}
26
27impl<T: Codec> KeyedVec for T {
28	fn to_keyed_vec(&self, prepend_key: &[u8]) -> Vec<u8> {
29		self.using_encoded(|slice| {
30			let mut r = prepend_key.to_vec();
31			r.extend(slice);
32			r
33		})
34	}
35}
parity_scale_codec/keyedvec.rs

parity_scale_codec/
keyedvec.rs
