Re: [PATCH 5/5] rust: error: Add from_kernel_result!() macro

[Martin Rodriguez Reboredo]

On 2/26/23 17:59, Miguel Ojeda wrote:
> On Sun, Feb 26, 2023 at 7:17 PM Boqun Feng <boqun.feng@xxxxxxxxx> wrote:
>>
>> My preference to function instead of macro here is because I want to
>> avoid the extra level of abstraction and make things explict, so that
>> users and reviewers can understand the API behavior solely based on
>> Rust's types, functions and closures: they are simpler than macros, at
>> least to me ;-)
> 
> There is one extra problem with the macro: `rustfmt` does not format
> the contents if called with braces (as we currently do).
> 
> So when I was cleaning some things up for v8, one of the things I did
> was run manually `rustfmt` on the blocks by removing the macro
> invocation, in commit 77a1a8c952e1 ("rust: kernel: apply `rustfmt` to
> `from_kernel_result!` blocks").
> 
> Having said that, it does format it when called with parenthesis
> wrapping the block, so we could do that if we end up with the macro.

Also rust-analyzer can't analyze the insides of a from_kernel_result!
block. Only thing it can do is to suggest a macro expansion. Plus, this
macro triggers a clippy lint on a redundant call on a closure. So it's a
bit annoying to work with.