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From:   Andreas Hindborg <nmi@metaspace.dk>
To:     Alice Ryhl <alice@ryhl.io>
Cc:     Gary Guo <gary@garyguo.net>, Miguel Ojeda <ojeda@kernel.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        =?utf-8?Q?Bj=C3=B6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        Benno Lossin <benno.lossin@proton.me>,
        Martin Rodriguez Reboredo <yakoyoku@gmail.com>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev
Subject: Re: [PATCH v2] rust: str: add conversion from `CStr` to `CString`
Date:   Mon, 15 May 2023 20:12:57 +0200
In-reply-to: <bb3bfbfb-0761-23b2-24e9-e5b4cb3ffac6@ryhl.io>
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Alice Ryhl <alice@ryhl.io> writes:

> On 5/8/23 13:41, Gary Guo wrote:
>> On Wed,  3 May 2023 14:10:16 +0000
>> Alice Ryhl <aliceryhl@google.com> wrote:
>> 
>>> These methods can be used to copy the data in a temporary c string into
>>> a separate allocation, so that it can be accessed later even if the
>>> original is deallocated.
>>>
>>> The API in this change mirrors the standard library API for the `&str`
>>> and `String` types. The `ToOwned` trait is not implemented because it
>>> assumes that allocations are infallible.
>> How about add a `TryToOwned` trait to the kernel crate and implement
>> that trait for `CStr` instead?
>
> Eh, I don't think it's worth it. It doesn't give anything new to the CStr api,
> and I think it's rather unlikely that someone will actually need to be generic
> over such a trait any time soon.

It is just as valid as having `From<&str>` and `ToOwned<&str>`. While it
does not add anything in terms of function, it carries intention. I
think we should consider adding it at some point.

BR Andreas