Expand description
Broom
An ergonomic tracing garbage collector that supports mark ’n sweep garbage collection.
Example
use broom::prelude::*;
// The type you want the heap to contain
pub enum Object {
Num(f64),
List(Vec<Handle<Self>>),
}
// Tell the garbage collector how to explore a graph of this object
impl Trace<Self> for Object {
fn trace(&self, tracer: &mut Tracer<Self>) {
match self {
Object::Num(_) => {},
Object::List(objects) => objects.trace(tracer),
}
}
}
// Create a new heap
let mut heap = Heap::default();
// Temporary objects are cheaper than rooted objects, but don't survive heap cleans
let a = heap.insert_temp(Object::Num(42.0));
let b = heap.insert_temp(Object::Num(1337.0));
// Turn the numbers into a rooted list
let c = heap.insert(Object::List(vec![a, b]));
// Change one of the numbers - this is safe, even if the object is self-referential!
*heap.get_mut(a).unwrap() = Object::Num(256.0);
// Create another number object
let d = heap.insert_temp(Object::Num(0.0));
// Clean up unused heap objects
heap.clean();
// a, b and c are all kept alive because c is rooted and a and b are its children
assert!(heap.contains(a));
assert!(heap.contains(b));
assert!(heap.contains(c));
// Because `d` was temporary and unused, it did not survive the heap clean
assert!(!heap.contains(d));