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Date: Thu, 25 Apr 2024 17:20:18 +0100
From: Gary Guo <gary@garyguo.net>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>, Alice Ryhl
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Subject: Re: [PATCH v6 4/4] rust: add abstraction for `struct page`
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On Thu, 18 Apr 2024 15:56:11 -0700
Boqun Feng <boqun.feng@gmail.com> wrote:
 
> Hmm.. here is the thing, having `&UnsafeCell<[u8]>` means having a `*mut
> [u8]>`, and it should always be safe to get a "length" of `*mut [u8]`,  
> right? I haven't found any method doing that, but the length should be
> just a part of fat pointer, so I think getting that is a defined
> behavior. But maybe I'm missing something.

You can just use `unsafe_cell.get().len()`. `len` method exists on
raw slice pointers, gated by the `slice_ptr_len` feature, which will
be stable in 1.79.0.

Best,
Gary