How to expose a Rust `Vec` to FFI?

Question

I\'m trying to construct a pair of elements:

• array: *mut T
• array_len: usize

array is intended to

Answer 1

You could use [T]::as_mut_ptr to obtain the *mut T pointer directly from Vec, Box<[T]> or any other DerefMut-to-slice types.

use std::mem;

let mut boxed_slice: Box<[T]> = vector.into_boxed_slice();

let array: *mut T = boxed_slice.as_mut_ptr();
let array_len: usize = boxed_slice.len();

// Prevent the slice from being destroyed (Leak the memory).
mem::forget(boxed_slice);