Trait trackable::Trackable

source ·

pub trait Trackable {
    type Event: From<Location>;

    // Required methods
    fn history(&self) -> Option<&History<Self::Event>>;
    fn history_mut(&mut self) -> Option<&mut History<Self::Event>>;

    // Provided methods
    fn track<F>(&mut self, f: F)
       where F: FnOnce() -> Self::Event { ... }
    fn in_tracking(&self) -> bool { ... }
}

Expand description

This trait allows to track an instance of an implementation type.

A trackable instance can have a tracking history that manages own backtrace-like (but more general) history for tracking.

You can add entries to the history by calling tracking macros(e.g., track!).

See TrackableError as a typical implementaion of this trait.

Examples

Defines a trackable type.

#[macro_use]
extern crate trackable;

use trackable::{Trackable, History, Location};

#[derive(Default)]
struct TrackableObject {
    history: History<Location>,
}
impl Trackable for TrackableObject {
    type Event = Location;
    fn history(&self) -> Option<&History<Self::Event>> {
        Some(&self.history)
    }
    fn history_mut(&mut self) -> Option<&mut History<Self::Event>> {
        Some(&mut self.history)
    }
}

fn main() {
    let o = TrackableObject::default();
    let o = track!(o);
    let o = track!(o, "Hello");
    let o = track!(o, "Hello {}", "World!");

    assert_eq!(format!("\n{}", o.history).replace('\\', "/"), r#"
HISTORY:
  [0] at src/lib.rs:23
  [1] at src/lib.rs:24 -- Hello
  [2] at src/lib.rs:25 -- Hello World!
"#);
}