Tracking Issue for `read_array`

[joshtriplett]

Feature gate: #![feature(read_array)]

This is a tracking issue for the read_array feature, which provides the Read::read_array method.

Public API

// std::io

impl Read {
    fn read_array<N: usize>(&mut self) -> Result<[u8; N]>
    where
        Self: Sized,
    {
        /* ... */
    }
}

Steps / History

(Remember to update the S-tracking-* label when checking boxes.)

• ACP: std::io::Read provides byte-order reading trait libs-team#691 (which inspired subsequent @rust-lang/libs-api design)
• Implementation: Implement Read::read_array #148850
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• None yet.

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩

[lyphyser]

I think this should return an ArrayVec equivalent (in which case the caller would chain a try_into() to get a plain array if they want).

Currently, it throws away data if there is some data available but not enough to fill the array, which is not a good interface.

It would be even more general to take an ArrayVec by &mut reference, and even more general some trait that can take both a Vec and an ArrayVec.

[Amanieu]

This is intended to be used like read_exact where you expect a certain number of bytes and any early EOF should be treated as an error (and the corresponding bytes simply dropped). If you need to handle early EOF then you should be using read instead of this.