# Rusty Object Notation
[![Build Status](https://travis-ci.org/ron-rs/ron.svg?branch=master)](https://travis-ci.org/ron-rs/ron)
[![Crates.io](https://img.shields.io/crates/v/ron.svg)](https://crates.io/crates/ron)
[![Docs](https://docs.rs/ron/badge.svg)](https://docs.rs/ron)
[![Gitter](https://badges.gitter.im/ron-rs/ron.svg)](https://gitter.im/ron-rs/ron)
RON is a simple readable data serialization format that looks similar to Rust syntax.
It's designed to support all of [Serde's data model](https://serde.rs/data-model.html), so
structs, enums, tuples, arrays, generic maps, and primitive values.
## Example
```
GameConfig( // optional struct name
window_size: (800, 600),
window_title: "PAC-MAN",
fullscreen: false,
mouse_sensitivity: 1.4,
key_bindings: {
"up": Up,
"down": Down,
"left": Left,
"right": Right,
// Uncomment to enable WASD controls
/*
"W": Up,
"A": Down,
"S": Left,
"D": Right,
*/
},
difficulty_options: (
start_difficulty: Easy,
adaptive: false,
),
)
```
## Why RON?
### Example in JSON
```json
{
"materials": {
"metal": {
"reflectivity": 1.0
},
"plastic": {
"reflectivity": 0.5
}
},
"entities": [
{
"name": "hero",
"material": "metal"
},
{
"name": "monster",
"material": "plastic"
}
]
}
```
Notice these issues:
1. Struct and maps are the same
- random order of exported fields
- annoying and inconvenient for reading
- doesn't work well with version control
- quoted field names
- too verbose
- no support for enums
2. No trailing comma allowed
3. No comments allowed
### Same example in RON
```rust
Scene( // class name is optional
materials: { // this is a map
"metal": (
reflectivity: 1.0,
),
"plastic": (
reflectivity: 0.5,
),
},
entities: [ // this is an array
(
name: "hero",
material: "metal",
),
(
name: "monster",
material: "plastic",
),
],
)
```
The new format uses `(`..`)` brackets for *heterogeneous* structures (classes),
while preserving the `{`..`}` for maps, and `[`..`]` for *homogeneous* structures (arrays).
This distinction allows us to solve the biggest problem with JSON.
Here are the general rules to parse the heterogeneous structures:
| no | no | tuple | `(a, b)` |
| yes/no | no | tuple struct | `Name(a, b)` |
| yes | no | enum value | `Variant(a, b)` |
| yes/no | yes | struct | `(f1: a, f2: b,)` |
### Specification
There is a very basic, work in progress specification available on
[the wiki page](https://github.com/ron-rs/ron/wiki/Specification).
A more formal and complete grammar is available [here](docs/grammar.md).
### Appendix
Why not XML?
- too verbose
- unclear how to treat attributes vs contents
Why not YAML?
- significant white-space
- specification is too big
Why not TOML?
- alien syntax
- absolute paths are not scalable
Why not XXX?
- if you know a better format, tell me!
## Tooling
Sublime Text: https://packagecontrol.io/packages/RON
Vim: https://github.com/ron-rs/ron.vim
## License
RON is dual-licensed under Apache-2.0 and MIT.