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Date:   Fri, 19 May 2023 09:42:14 +0000
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Subject: Re: [PATCH v1 1/2] rust: specify when `ARef` is thread safe
From:   Alice Ryhl <aliceryhl@google.com>
To:     boqun.feng@gmail.com
Cc:     alex.gaynor@gmail.com, aliceryhl@google.com,
        benno.lossin@proton.me, bjorn3_gh@protonmail.com, gary@garyguo.net,
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On 5/18/23 23:24, Boqun Feng wrote:
> On Wed, May 17, 2023 at 09:59:04AM +0000, Alice Ryhl wrote:
>> +// SAFETY: It is safe to send `ARef<T>` to another thread when the underlying `T` is `Sync` because
>> +// it effectively means sharing `&T` (which is safe because `T` is `Sync`); additionally, it needs
>> +// `T` to be `Send` because any thread that has an `ARef<T>` may ultimately access `T` directly, for
>
> Does the "ultimately access `T` directly" here imply mutably or
> exclusively? If so, it makes sense to me to call it out. I'm trying to
> make sure we can agree on some "common terminologies" ;)

It means "access using a mutable reference". I agree that "directly" is a bit
unclear - I copied it from the safety comment on Arc.

Alice