Re: [PATCH v10 4/6] rust: enable `clippy::as_underscore` lint

[Boqun Feng]

On Fri, Apr 18, 2025 at 11:37:20AM -0400, Tamir Duberstein wrote:
> In Rust 1.63.0, Clippy introduced the `as_underscore` lint [1]:
> 
> > The conversion might include lossy conversion or a dangerous cast that
> > might go undetected due to the type being inferred.
> >
> > The lint is allowed by default as using `_` is less wordy than always
> > specifying the type.
> 
> Always specifying the type is especially helpful in function call
> contexts where the inferred type may change at a distance. Specifying
> the type also allows Clippy to spot more cases of `useless_conversion`.
> 
> The primary downside is the need to specify the type in trivial getters.
> There are 4 such functions: 3 have become slightly less ergonomic, 1 was
> revealed to be a `useless_conversion`.
> 
> While this doesn't eliminate unchecked `as` conversions, it makes such
> conversions easier to scrutinize.  It also has the slight benefit of
> removing a degree of freedom on which to bikeshed. Thus apply the
> changes and enable the lint -- no functional change intended.
> 
> Link: https://rust-lang.github.io/rust-clippy/master/index.html#as_underscore [1]
> Reviewed-by: Benno Lossin <benno.lossin@xxxxxxxxx>

Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx>

Regards,
Boqun

> Signed-off-by: Tamir Duberstein <tamird@xxxxxxxxx>
[...]