#vec #nightly #allocator #slice #heap-allocated #array #interface

no-std cl-generic-vec

a vector implementation that can be used in no_std envioronments

9 unstable releases (3 breaking)

0.4.0 Mar 9, 2022
0.3.4 Jan 11, 2022
0.2.1 Jan 10, 2022
0.1.4 Nov 10, 2021
0.1.0 Mar 9, 2022

#225 in Memory management

43 downloads per month
Used in 2 crates


2.5K SLoC

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A vector that can store items anywhere: in slices, arrays, or the heap!

GenericVec has complete parity with Vec, and even provides some features that are only in nightly on std (like GenericVec::drain_filter), or a more permissive interface like GenericVec::retain. In fact, you can trivially convert a Vec to a HeapVec and back!

This crate is no_std compatible, just turn off all default features.


  • std (default) - enables you to use an allocator, and
  • alloc - enables you to use an allocator, for heap allocated storages (like Vec)
  • nightly - enables you to use array ([T; N]) based storages

Basic Usage


SliceVec stores an uninit slice buffer, and they store all of thier values in that buffer.

use cl_generic_vec::SliceVec;

let mut uninit_buffer = uninit_array::<_, 16>();
let mut slice_vec = SliceVec::new(&mut uninit_buffer);

assert_eq!(slice_vec, [10]);


ArrayVec is just like the slice versions, but since they own their data, they can be freely moved around, unconstrained. You can also create a new ArrayVec without passing in an existing buffer, unlike the slice versions.

use cl_generic_vec::ArrayVec;

let mut array_vec = ArrayVec::<i32, 16>::new();


assert_eq!(array_vec, [10, 20, 30]);


A HeapVec is just Vec, but built atop GenericVec, meaning you get all the features of GenericVec for free! But this requries either the alloc or std feature to be enabled.

use cl_generic_vec::{HeapVec, gvec};
let mut vec: HeapVec<u32> = gvec![1, 2, 3, 4];
assert_eq!(vec.capacity(), 4);
vec.extend(&[5, 6, 7, 8]);

assert_eq!(vec, [1, 2, 3, 4, 5, 6, 7, 8]);

vec.try_push(5).expect_err("Tried to push past capacity!");


On nightly

  • a number of optimizations are enabled
  • some diagnostics become better

Note on the documentation: if the feature exists on Vec, then the documentation is either exactly the same as Vec or slightly adapted to better fit GenericVec

Note on implementation: large parts of the implementation came straight from Vec so thanks for the amazing reference std!

Current version: 0.1.2

License: MIT/Apache-2.0

No runtime deps