Crate unsized_vec

UnsizedVec<T>, like Vec<T>, is a contiguous growable array type with heap-allocated contents. Unlike Vec<T>, it can store unsized values.

Vectors have O(1) indexing, amortized O(1) push (to the end) and O(1) pop (from the end). When T is Sized, they use one heap allocation; when it is not, they use two.

This crate is nightly-only and experimental.

Examples

You can explicitly create an UnsizedVec with UnsizedVec::new:

let v: UnsizedVec<i32> = UnsizedVec::new();

…or by using the unsize_vec! macro:

let v: UnsizedVec<[u32]> = unsize_vec![];

let v: UnsizedVec<dyn Debug> = unsize_vec![1_u32, "hello!", 3.0_f64, (), -17_i32];

You can push or push_unsize values onto the end of a vector (which will grow the vector as needed):

let mut v: UnsizedVec<dyn Debug> = unsize_vec![1_u32, "hello!", 3.0_f64, (), -17_i32];

v.push_unsize(3);

Popping values works in much the same way:

let mut v: UnsizedVec<dyn Debug> = unsize_vec![1_u32, "hello!"];

// "hello!" is copied directly into a new heap allocation
let two: Option<Box<dyn Debug>> = v.pop_into().map(box_new_with);

Vectors also support indexing (through the Index and IndexMut traits):

let mut v: UnsizedVec<dyn Debug> = unsize_vec![1_u32, "hello!", [(); 0]];
let greeting = &v[1];
dbg!(greeting);

Macros

• unsize_vec
  Like unsized_vec, but unsizes its arguments using the Unsize trait.
• unsized_vec
  Like the standard library’s vec macro. Accepts both raw unsized Ts and Emplacable<T,_>s.

Structs

• TryReserveError
  The error type for try_reserve methods.
• UnsizedIter
  The iterator returned by UnsizedVec::iter.
• UnsizedIterMut
  The iterator returned by UnsizedVec::iter_mut.
• UnsizedVec
  Like Vec, but can store unsized values.