Crate bump_into

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Expand description

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]);

Modules

Types implementing Into<Option<Layout>>, for use with BumpInto::available_spaces and BumpInto::alloc_space.

Macros

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

Structs

A bump allocator sourcing space from an &mut [MaybeUninit].