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Subject: Re: [PATCH v9 12/27] rust: add `kernel` crate
From:   comex <comexk@gmail.com>
In-Reply-To: <20220920233947.0000345c@garyguo.net>
Date:   Wed, 21 Sep 2022 02:42:18 -0400
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To:     Gary Guo <gary@garyguo.net>
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> On Sep 20, 2022, at 6:39 PM, Gary Guo <gary@garyguo.net> wrote:
>=20
> 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 =
=E2=80=99negative 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.=