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From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Thu, 8 Jul 2021 16:33:48 +0200
Message-ID: <CAMuHMdVeFtRp5tUbErqqyUXz2Mrz8kCc7XbYs4Y6vr8n50A_jA@mail.gmail.com>
Subject: Re: [TECH TOPIC] Rust for Linux
To: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
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"

Hi Miguel,

On Thu, Jul 8, 2021 at 4:28 PM Miguel Ojeda
<miguel.ojeda.sandonis@gmail.com> wrote:
> On Thu, Jul 8, 2021 at 4:18 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > 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

What if I would ignore that? I.e.

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

?

Please forgive my silly questions, I'm a Rust newbie ;-)

>     }

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds