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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Sun, 26 Feb 2023 14:40:44 +0100
Message-ID: <CANiq72m8jmW0WEmscR3+C2aiL+FCzYZXj2SrfruCu4UB98ZCYg@mail.gmail.com>
Subject: Re: [PATCH 5/5] rust: error: Add from_kernel_result!() macro
To:     Boqun Feng <boqun.feng@gmail.com>
Cc:     Gary Guo <gary@garyguo.net>, Asahi Lina <lina@asahilina.net>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Sven Van Asbroeck <thesven73@gmail.com>,
        Fox Chen <foxhlchen@gmail.com>, rust-for-linux@vger.kernel.org,
        linux-kernel@vger.kernel.org, asahi@lists.linux.dev
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On Sun, Feb 26, 2023 at 3:22=E2=80=AFAM Boqun Feng <boqun.feng@gmail.com> w=
rote:
>
> Hmm.. looks like the `?` only "propagating them (the errors) to the
> calling *function*":
>
>         https://doc.rust-lang.org/reference/expressions/operator-expr.htm=
l#the-question-mark-operator
>
> , so this doesn't work as we expect:
>
>         https://play.rust-lang.org/?version=3Dstable&mode=3Ddebug&edition=
=3D2021&gist=3D64c9039e1da2c436f9f4f5ea46e97e90
>
> Hope I didn't miss something subtle here..

There is `feature(try_blocks)` [1] for that:

    https://play.rust-lang.org/?version=3Dnightly&mode=3Ddebug&edition=3D20=
21&gist=3D8f40663d2ad51e04a13f2da5c4580fc0

[1] https://github.com/rust-lang/rust/issues/31436.

Cheers,
Miguel