Crate serde_hashkey

Serde-based in-memory key serialization.

This allows any serde-serializable type to be converted into a Value which implements PartialEq, Eq, ParialOrd, Ord, and Hash. The only limitation is that the type can't serialize floating point values. This might be lifted in the future by specifying policies for dealing with non-finite values.

Key is useful because it allows for a form of type-erasure. Let's say you want to build a generic in-memory key-value store where you want to store arbitrary serde-serializable keys. This is typical for things like caches or dependency injection frameworks.

Examples

You can run this example with cargo run --example book

use serde_derive::{Deserialize, Serialize};
use serde_hashkey::{from_key, to_key, Error, Key};
use std::{collections::HashMap, error};
 
#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
struct Author {
    name: String,
    age: u32,
}
 
#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
struct Book {
    title: String,
    author: Author,
}
 
fn main() -> Result<(), Box<dyn error::Error>> {
    let book = Book {
        title: String::from("Birds of a feather"),
        author: Author {
            name: String::from("Noah"),
            age: 42,
        },
    };
 
    let key = to_key(&book)?;
 
    let mut ratings = HashMap::new();
    ratings.insert(key.clone(), 5);
 
    println!("ratings: {:?}", ratings);
 
    println!(
        "book as json (through key): {}",
        serde_json::to_string_pretty(&key)?
    );
 
    println!(
        "book as json (through original object): {}",
        serde_json::to_string_pretty(&book)?
    );
 
    Ok(())
}

Enums

Error
Integer
Key

Functions

from_key	Convert a Key into a type T
to_key	Convert the given type to a value.

Type Definitions

Result