Crate jsone 

Serde helpers for values that need a JSON representation which JavaScript can decode without losing precision.

This crate exposes a single wrapper type, Jsone<T> which wraps any field or type, and handles the lossless serialization and deserialization of values in Rust. You must pair this with the frontend encoder or decoder to turn the response back to regular JavaScript.

Be aware if the decoder detects a bigint value, it will may return a JS BigInt object instead of a number so your code must be able to handle this!

Supported values

We support losslessly serializing and deserializing:

• special-case floating-point numbers like f64::NAN, f64::INFINITY, f64::NEG_INFINITY
• Rust integer types which are larger than Number.MAX_SAFE_INTEGER or smaller than Number.MIN_SAFE_INTEGER

We do this by encoding them into a special JSON struct like:

• For special-cases we use the form { "$$jsone$remap$$": 1 } where each number represents a known special case.
• For integer outside safe range: { "$$jsone$remap$$": "12345678901234567890" }

The JS decoder can find this object key and replace the whole object with the correct value, making end to end lossless serialization and deserialization possible.

Example

use jsone::Jsone;
use serde::{Deserialize, Serialize};

#[derive(Debug, Deserialize, PartialEq, Serialize)]
struct Payload {
    id: Jsone<i32>,
}

let json = serde_json::to_string(&Payload { id: Jsone(42) }).unwrap();
assert_eq!(json, r#"{"id":42}"#);

let payload: Payload = serde_json::from_str(&json).unwrap();
assert_eq!(payload.id, Jsone(42));

Structs

Jsone

Serde wrapper that applies the remap logic.

Constants

JS_RUNTIME

The JavaScript runtime for encoding and decoding.