Crate serde_cow 

A small library with a Cow wrappers that implements serde::Deserialize in the ways that should be expected.

By default, Cow is always deserialized to the Cow::Owned variant due to a lack of specialisation, but this library provides CowStr and CowBytes which deserialize to Cow::Borrowed if possible, borrowing from the original data.

Example

use std::borrow::Cow;

use serde_cow::CowStr;

let source = r#""Hello World""#;

let normal: Cow<str> = serde_json::from_str(source).unwrap();
assert!(matches!(normal, Cow::Owned(_))); // Wasteful!

let efficent: CowStr = serde_json::from_str(source).unwrap();
assert!(matches!(efficent.0, Cow::Borrowed(_))); // Zero copy!

Minimum Supported Rust Version

This is currently 1.56 and is considered a breaking change to increase.

Structs

CowBytes

A wrapper around Cow<[u8]> to implement serde::Deserialize in the expected way.

CowStr

A wrapper around Cow<str> to implement serde::Deserialize in the expected way.