🔑 KeyPaths & CasePaths in Rust

Key paths and case paths provide a safe, composable way to access and modify nested data in Rust. Inspired by Swift’s KeyPath / CasePath system, this feature rich crate lets you work with struct fields and enum variants as first-class values.

Derive Macro Generated Methods for Locks

The derive macro generates helper methods for Arc<Mutex<T>> and Arc<RwLock<T>> fields:

use std::sync::Arc;
use parking_lot::RwLock;
use keypaths_proc::Kp;

#[derive(Kp)]
#[Writable]
struct Container {
    // This uses parking_lot::RwLock (default)
    data: Arc<RwLock<DataStruct>>,
    
    // This uses std::sync::RwLock (explicit)
    std_data: Arc<std::sync::RwLock<DataStruct>>,
}

#[derive(Kp)]
#[Writable]
struct DataStruct {
    name: String,
}

fn main() {
    let container = Container { /* ... */ };
    
    // Using generated _fr_at() for parking_lot (default)
    Container::data_fr_at(DataStruct::name_r())
        .get(&container, |value| {
            println!("Name: {}", value);
        });
    
    // Using generated _fw_at() for parking_lot (default)
    Container::data_fw_at(DataStruct::name_w())
        .get_mut(&container, |value| {
            *value = "New name".to_string();
        });
    
    // Using generated _fr_at() for std::sync::RwLock (explicit)
    Container::std_data_fr_at(DataStruct::name_r())
        .get(&container, |value| {
            println!("Name: {}", value);
        });
}

📜 License

• Mozilla Public License 2.0