Struct konst::alloc_type::COW_SLICE_NEW

pub struct COW_SLICE_NEW<'a, T: Clone + 'a>(_);

This is supported on crate feature alloc only.

An empty Cow<'_, [T]>. Usable to construct a [Cow<'_, [T]>; N].

As of Rust 1.51.0, [Cow::Borrowed(&[][..]); LEN] is not valid, because Cow<'_, [T]> isn’t copy, but [CONST; LEN] does work, like in the example below.

Example

use konst::alloc_type::COW_SLICE_NEW;

use std::borrow::Cow;

const SLICES: [Cow<'_, [u64]>; 6] = [COW_SLICE_NEW::<u64>::V; 6];

let mut cows = SLICES;

[3, 5, 8, 13, 21, 34].iter().copied()
    .enumerate()
    .filter(|(i, _)| i % 2 != 0 )
    .for_each(|(i, v)|{
        cows[i].to_mut().push(v)
    });

assert_eq!(cows, [&[][..], &[5], &[], &[13], &[], &[34]])

Implementations

impl<'a, T: Clone + 'a> COW_SLICE_NEW<'a, T>

pub const V: Cow<'a, [T]>

The value that this constructs.