This Rust module provides a memory allocation Arena for types that implement Copy.

Documentation

Examples

Basic usage is as follows:

```rust extern crate copy_arena;

use copy_arena::Arena;

let mut arena = Arena::new(); let mut allocator = arena.allocator();

let a: &mut i32 = allocator.alloc(5); let b: &mut f64 = allocator.allocdefault(); let c: &mut [u8] = allocator.allocslice(b"some text"); let b: &mut [usize] = allocator.allocslicefn(10, |idx| idx + 1); let e: &mut [u32] = allocator.allocslicedefault(10); ```

This could be used for building a tree structure without heap allocations for each node:

```rust use copy_arena::{Arena, Allocator};

[derive(Copy, Clone)]

struct Tree<'a> { left: Option<&'a Tree<'a>>, right: Option<&'a Tree<'a>>, content: u32 }

fn buildlittletree<'a>(allocator: &mut Allocator<'a>) -> &'a Tree<'a> { let left = allocator.alloc(Tree { left: None, right: None, content: 8 }); let right = allocator.alloc(Tree { left: None, right: None, content: 16 }); let parent = allocator.alloc(Tree { left: Some(left), right: Some(right), content: 13 });

parent

}

[test]

fn make_tree() { let mut arena = Arena::new(); let mut allocator = arena.allocator();

let root = build_little_tree(&mut allocator);
assert_eq!(root.content, 13);
assert_eq!(root.left.unwrap().content, 8);
assert_eq!(root.right.unwrap().content, 16);

} ```

Compared to std::arena::Arena

This differs from the (unstable) Arena in Rust's standard library in a couple of ways: