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From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date: Thu, 8 Jul 2021 16:28:24 +0200
Message-ID: <CANiq72kGBz=ohqS_YbTGc_CuRGxd-xmim-RT=pHHjMzi=39gSw@mail.gmail.com>
Subject: Re: [TECH TOPIC] Rust for Linux
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Wedson Almeida Filho <wedsonaf@google.com>, Jan Kara <jack@suse.cz>, Greg KH <greg@kroah.com>, 
	James Bottomley <James.Bottomley@hansenpartnership.com>, 
	Julia Lawall <julia.lawall@inria.fr>, 
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>, 
	Linus Walleij <linus.walleij@linaro.org>, Roland Dreier <roland@kernel.org>, ksummit@lists.linux.dev
Content-Type: text/plain; charset="UTF-8"

On Thu, Jul 8, 2021 at 4:18 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Exactly.

I had a feeling... :)

> Let's assume the caller access a member of the object regardless.
> What happens?

That is the key: they cannot access it to begin with because the
returned `Option` is empty, so there is not even an object you can
"access", thus asking "what happens?" does not have a meaning.

In code:

    pub fn f(weak: Weak<i32>) {
        let strong = weak.upgrade();

        if let Some(content) = strong {
            println!("{}", content);
        }

        // There is no `content` here, so you cannot do anything with it
    }

Cheers,
Miguel