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// SPDX-License-Identifier: GPL-2.0 //! Additional (and temporary) slice helpers. /// Extension trait providing a portable version of [`as_flattened`] and/// [`as_flattened_mut`].////// In Rust 1.80, the previously unstable `slice::flatten` family of methods/// have been stabilized and renamed from `flatten` to `as_flattened`.////// This creates an issue for as long as the MSRV is < 1.80, as the same functionality is provided/// by different methods depending on the compiler version.////// This extension trait solves this by abstracting `as_flatten` and calling the correct method/// depending on the Rust version.////// This trait can be removed once the MSRV passes 1.80.////// [`as_flattened`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened/// [`as_flattened_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened_mut#[cfg(not(CONFIG_RUSTC_HAS_SLICE_AS_FLATTENED))]pub trait AsFlattened<T> {    /// Takes a `&[[T; N]]` and flattens it to a `&[T]`.    ///    /// This is an portable layer on top of [`as_flattened`]; see its documentation for details.    ///    /// [`as_flattened`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened    fn as_flattened(&self) -> &[T];     /// Takes a `&mut [[T; N]]` and flattens it to a `&mut [T]`.    ///    /// This is an portable layer on top of [`as_flattened_mut`]; see its documentation for details.    ///    /// [`as_flattened_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened_mut    fn as_flattened_mut(&mut self) -> &mut [T];} #[cfg(not(CONFIG_RUSTC_HAS_SLICE_AS_FLATTENED))]impl<T, const N: usize> AsFlattened<T> for [[T; N]] {    #[allow(clippy::incompatible_msrv)]    fn as_flattened(&self) -> &[T] {        self.flatten()    }     #[allow(clippy::incompatible_msrv)]    fn as_flattened_mut(&mut self) -> &mut [T] {        self.flatten_mut()    }}