json-as

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    AssemblyScript - v1.0.0-alpha.4
  

Contents

• About
• Installation
• Usage
• Examples
• Performance
• License
• Contact

About

Installation

npm install json-as@1.0.0-alpha.3

Add the --transform to your asc command (e.g. in package.json)

--transform json-as

Alternatively, add it to your asconfig.json

{
  // ...
  "options": {
    "transform": ["json-as/transform"]
  }
}

If you'd like to see the code that the transform generates, run with JSON_DEBUG=true

Usage

import { JSON } from "json-as";

@json
class Vec3 {
  x: f32 = 0.0;
  y: f32 = 0.0;
  z: f32 = 0.0;
}

@json
class Player {
  @alias("first name")
  firstName!: string;
  lastName!: string;
  lastActive!: i32[];
  // Drop in a code block, function, or expression that evaluates to a boolean
  @omitif((self: Player) => self.age < 18)
  age!: i32;
  @omitnull()
  pos!: Vec3 | null;
  isVerified!: boolean;
}

const player: Player = {
  firstName: "Jairus",
  lastName: "Tanaka",
  lastActive: [2, 7, 2025],
  age: 18,
  pos: {
    x: 3.4,
    y: 1.2,
    z: 8.3
  },
  isVerified: true
};

const serialized = JSON.stringify<Player>(player);
const parsed = JSON.parse<Player>(serialized);

console.log("Serialized: " + serialized);
console.log("Parsed: " + JSON.stringify(parsed));

Examples

Classes can even have inheritance. Here's a nasty example

@json
class Base {}

@json
class Vec1 extends Base {
  x: f32 = 1.0;
}
@json
class Vec2 extends Vec1 {
  y: f32 = 2.0;
}
@json
class Vec3 extends Vec2 {
  z: f32 = 3.0;
}

const arr: Base[] = [
  new Vec1(),
  new Vec2(),
  new Vec3()
];

const serialized = JSON.stringify(arr);
// [{"x":1.0},{"x":1.0,"y":2.0},{"y":2.0,"x":1.0,"z":3.0}]
const parsed = JSON.parse<Base[]>(serialized);

You can also add it to your asconfig.json

{
  // ...
  "options": {
    "transform": ["json-as/transform"]
  }
}

If you use this project in your codebase, consider dropping a star. I would really appreciate it!

📃 License

This project is distributed under an open source license. You can view the full license using the following link: License

📫 Contact

Please send all issues to GitHub Issues and to converse, please send me an email at [e-mail]

• Email: Send me inquiries, questions, or requests at [e-mail]
• GitHub: Visit the official GitHub repository Here
• Website: Visit my official website at jairus.dev
• Discord: Converse with me on My Discord or on the AssemblyScript Discord Server

Changelog

2025-02-13 - 1.0.0-alpha.4

• feat: reintroduce support for Box<T>-wrapped primitive types
• tests: add extensive tests to all supported types
• fix: 6-byte keys being recognized on deserialize
• perf: take advantage of aligned memory to use a single 64-bit load on 6-byte keys
• fix: bs.proposeSize() should increment stackSize by size instead of setting it
• fix: allow runtime to manage bs.buffer
• fix: memory leaks in bs module
• fix: add (possibly temporary) JSON.Memory.shrink() to shrink memory in bs
• perf: prefer growing memory by nextPowerOf2(size + 64) for less reallocations
• tests: add boolean tests to Box<T>
• fix: serialization of non-growable data types should grow bs.stackSize