A dynamically typed value with fast downcasting.

Provides a Dynamic type, which contains a dynamically typed value. Dynamic is similar to Any from std::any::Any, except that downcasting does not involve any virtual calls since the TypeId of the contained value is pre-computed.

extern crate dynamic;

use dynamic::Dynamic;

fn main() {
    // Create a new Dynamic value.
    let x = Dynamic::new(100usize);

    // If we try to downcast to the wrong type it will not work.
    assert_eq!(x.downcast_ref::<i32>(), None);

    // If we downcast to the right type, we get access.
    assert_eq!(x.downcast_ref::<usize>(), Some(&100usize));
}

Use the crates.io repository; add this to your Cargo.toml along with the rest of your dependencies:

[dependencies]
dynamic = "0.2"

Jonathan Reem is the primary author and maintainer of dynamic.

MIT