kvstruct

A minimalistic, zero-dependency Rust library for generating JSON-like representations of your structs.

Instead of relying on heavy procedural macros or external dependencies like serde, kvstruct provides a simple declarative macro (json!) that wraps your struct definition and automatically implements a to_json() method for it.

Features

• Zero Dependencies: Pure Rust, no external crates required. Fast compile times.
• Declarative Macro: Uses a simple macro_rules! to generate serialization code.
• Easy to Use: Just wrap your struct definition in the json! macro.
• Preserves Struct Attributes: Fully supports visibility modifiers (e.g., pub), attributes (e.g., #[derive(...)]), and standard types.

Installation

cargo add [email protected]

Usage

Use the json! macro to define your struct, which will automatically implement the Jsonfy trait.

use kvstruct::{json, Jsonfy};

json! {
    #[derive(Debug)]
    pub struct User {
        pub name: String,
        pub age: u32,
        pub friends: Vec<String>,
    }
}

fn main() {
    let user = User {
        name: String::from("Healer"),
        age: 20,
        friends: vec![String::from("Mskillder", String::from("Patrick"))] ,
    };

    // Serialize the struct to a formatted JSON string
    let json_string = user.to_json();
    println!("{}", json_string);
}

Important Note on Serialization

Behind the scenes, the json! macro uses the std::fmt::Debug ({:?}) representation to serialize the values of your struct fields. Therefore, all field types must implement Debug. Note that output fields are wrapped in double quotes. For compound types like vectors or tuples, backslashes are removed resulting in visually clean output, avoiding "[\"A\"]" in favor of "["A"]".

While this works nicely for simple structures and debugging purposes, please be aware this output is a custom JSON-like format and complex nested structures might not produce strict, RFC-compliant JSON.

License

MIT OR Apache-2.0