10 unstable releases (3 breaking)
Uses new Rust 2024
new 0.4.2 | May 1, 2025 |
---|---|
0.4.1 | Apr 30, 2025 |
0.3.1 | Mar 27, 2025 |
0.2.0 | Feb 17, 2023 |
0.1.0 | Feb 1, 2022 |
#795 in Rust patterns
8,991 downloads per month
Used in 4 crates
74KB
2K
SLoC
CapWriter
A fast serializer for Vec
/slice with a lightweight cap" header.
Usage
Save
& Load
use capwriter::{Save, Load};
let original: Vec<i32> = vec![1, 2, 3, 4, 5];
// (1) Save
let mut buf = Vec::new();
original.save_as_ne(&mut buf).unwrap();
assert_eq!(original.encoded_len(), buf.len()); // size can be estimated
// (2) Load
let decoded = Vec::<i32>::load_as_ne(&mut &buf[..]).unwrap();
assert_eq!(original, decoded);
AsyncSave
& AsyncLoad
(on async-tokio
feature)
use capwriter::{AsyncSave, AsyncLoad};
use std::pin::Pin;
let vec_to_save: Vec<i32> = vec![1, 2, 3, 4, 5];
// (1) Save
let mut buffer = Vec::new();
vec_to_save.save_as_ne(Pin::new(&mut buffer)).await.unwrap();
// (2) Load
let vec_loaded = Vec::<i32>::load_as_ne(Pin::new(&mut &buffer[..])).await.unwrap();
assert_eq!(vec_to_save, vec_loaded);
Supported types
- trait
Save
can be used in:Vec<T>
,&[T]
,[T; usize]
- trait
Load
can be used in:Vec<T>
,[T; usize]
- For the
T
:()
,u8
,u16
,u32
,u64
,u128
,usize
,i8
,i16
,i32
,i64
,i128
,isize
,f32
,f64
,Option<T>
,PhantomData<T>
- impl the trait
Pod (Plain Old Data)
inbytemuck
(https://crates.io/crates/bytemuck) crate.
- impl the trait
Bench
-
Run bench with
cargo bench
-
For
Vec<usize>
length of 10,000,000 (for v0.2.0)capwriter with serialized data save 21.483 ms 25.506 ms load 12.001 ms 77.664 ms
Notes
Cap size
Since v0.4, the header uses u64
instead of usize
so that data are portable across 32- and 64-bit platforms.
Safety
capwriter
does no runtime type checking. Supplying a buffer whose contents do not match the expected T
results in undefined behaviour (panic, corrupted data, or excessive allocation). Ensure that the producer and consumer agree on the exact element type.
Dependencies
~0.1–7.5MB
~24K SLoC