Crate bump_into

A no_std bump allocator sourcing space from a user-provided mutable slice rather than from a global allocator, making it suitable for use in embedded applications and tight loops.

Drop behavior

Values held in BumpInto allocations are never dropped. If they must be dropped, you can use core::mem::ManuallyDrop::drop or core::ptr::drop_in_place to drop them explicitly (and unsafely). In safe code, you can allocate an Option and drop the value inside by overwriting it with None.

Example

use bump_into::{self, BumpInto};

// allocate 64 bytes of uninitialized space on the stack
let mut bump_into_space = bump_into::space_uninit!(64);
let bump_into = BumpInto::from_slice(&mut bump_into_space[..]);

// allocating an object produces a mutable reference with
// a lifetime borrowed from `bump_into_space`, or gives
// back its argument in `Err` if there isn't enough space
let number: &mut u64 = bump_into
    .alloc_with(|| 123)
    .ok()
    .expect("not enough space");
assert_eq!(*number, 123);
*number = 50000;
assert_eq!(*number, 50000);

// slices can be allocated as well
let slice: &mut [u16] = bump_into
    .alloc_n_with(5, core::iter::repeat(10))
    .expect("not enough space");
assert_eq!(slice, &[10; 5]);
slice[2] = 100;
assert_eq!(slice, &[10, 10, 100, 10, 10]);

Macros

space_uninit	Creates an uninitialized array of MaybeUninit without allocating, suitable for taking a slice of to pass into BumpInto::from_slice.
space_uninit_aligned	Creates an uninitialized array of one MaybeUninit without allocating, with the given size and alignment, suitable for taking a slice of to pass into BumpInto::from_slice.
space_zeroed	Creates a zeroed array of MaybeUninit without allocating, suitable for taking a slice of to pass into BumpInto::from_slice.
space_zeroed_aligned	Creates a zeroed array of one MaybeUninit without allocating, with the given size and alignment, suitable for taking a slice of to pass into BumpInto::from_slice.

Structs

AlignOf	A zero-sized struct that becomes core::mem::align_of::<T>() when converted using Into<usize>.
BumpInto	A bump allocator sourcing space from an &mut [MaybeUninit].
SizeOf	A zero-sized struct that becomes core::mem::size_of::<T>() when converted using Into<usize>.