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Date:   Wed, 21 Sep 2022 07:19:16 -0700
From:   Boqun Feng <boqun.feng@gmail.com>
To:     comex <comexk@gmail.com>
Cc:     Gary Guo <gary@garyguo.net>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
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Subject: Re: [PATCH v9 12/27] rust: add `kernel` crate
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On Wed, Sep 21, 2022 at 02:42:18AM -0400, comex wrote:
> 
> 
> > On Sep 20, 2022, at 6:39 PM, Gary Guo <gary@garyguo.net> wrote:
> > 
> > It should be noted however, atomic context is not something that a
> > token can represent. You can only use tokens to restrict what you *can*
> > do, but not what you *can't* do. There is no negative reasoning with
> > tokens, you can't create a function that can only be called when you
> > don't have token.
> 
> On the other hand, it ought to be feasible to implement that kind of
> ’negative reasoning' as a custom lint.  It might not work as well as
> something built into the language, but it should work decently well,
> and could serve as a prototype for a future built-in feature.

Interesting, do you have an example somewhere?

Regards,
Boqun