The Interact dependency is needed:

[dependencies]
interact = "0.3"

• The a crate's top level, extern crate interact is needed.
• At places #[derive(Interact)] is needed, import the needed proc macro: use interact::Interact;

An example:

# #![allow(unused_variables)]
#fn main() {
extern crate interact;

use interact::Interact;

#[derive(Interact)]
struct Point {
    x: i32,
    y: i32,
}
#}