without-alloc 0.2.2

Replacements for `Box`, `Rc`, `Vec`, .. without `alloc`
Documentation

without-alloc

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Dynamic data structures that do not require a global allocator.

Usage

This allows creating dynamic and recursive data structures without dynamic allocations. The example below makes use of the static-alloc crate to build a list with static lifetime based on dynamic data. As local memory pools for fixed capacity FixedVec:

use static_alloc::Bump;
use without_alloc::{FixedVec, alloc::LocalAllocLeakExt};

let mut pool: Bump<[usize; 16]> = Bump::uninit();
// Allocate a vector with capacity of 16 from the slab.
let mut vector = pool.fixed_vec(16).unwrap();

let mut num = 0;
// Push mutable ref, not `'static`, `Copy` nor `Clone`!
vector.push(&mut num);
*vector[0] = 42;

drop(vector);
assert_eq!(num, 42);

This might be handy if you want to chain boot another kernel and pass it a linked list describing the platform.

use static_alloc::Bump;
use without_alloc::{Box, alloc::LocalAllocLeakExt};

enum List {
    Nil,
    Cons(u8, Box<'static, List>),
}

static SLAB: Bump<[u8; 1024]> = Bump::uninit();

let base = SLAB.boxed(List::Nil).unwrap();
let one = SLAB.boxed(List::Cons(0, base)).unwrap();
let two = SLAB.boxed(List::Cons(1, one)).unwrap();