// SPDX-License-Identifier: Apache-2.0 OR MIT //! Collection types. #![stable(feature = "rust1", since = "1.0.0")] #[cfg(not(no_global_oom_handling))]pub mod binary_heap;#[cfg(not(no_global_oom_handling))]mod btree;#[cfg(not(no_global_oom_handling))]pub mod linked_list;#[cfg(not(no_global_oom_handling))]pub mod vec_deque; #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]pub mod btree_map {    //! An ordered map based on a B-Tree.    #[stable(feature = "rust1", since = "1.0.0")]    pub use super::btree::map::*;} #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]pub mod btree_set {    //! An ordered set based on a B-Tree.    #[stable(feature = "rust1", since = "1.0.0")]    pub use super::btree::set::*;} #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]#[doc(no_inline)]pub use binary_heap::BinaryHeap; #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]#[doc(no_inline)]pub use btree_map::BTreeMap; #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]#[doc(no_inline)]pub use btree_set::BTreeSet; #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]#[doc(no_inline)]pub use linked_list::LinkedList; #[cfg(not(no_global_oom_handling))]#[stable(feature = "rust1", since = "1.0.0")]#[doc(no_inline)]pub use vec_deque::VecDeque; use crate::alloc::{Layout, LayoutError};use core::fmt::Display; /// The error type for `try_reserve` methods.#[derive(Clone, PartialEq, Eq, Debug)]#[stable(feature = "try_reserve", since = "1.57.0")]pub struct TryReserveError {    kind: TryReserveErrorKind,} impl TryReserveError {    /// Details about the allocation that caused the error    #[inline]    #[must_use]    #[unstable(        feature = "try_reserve_kind",        reason = "Uncertain how much info should be exposed",        issue = "48043"    )]    pub fn kind(&self) -> TryReserveErrorKind {        self.kind.clone()    }} /// Details of the allocation that caused a `TryReserveError`#[derive(Clone, PartialEq, Eq, Debug)]#[unstable(    feature = "try_reserve_kind",    reason = "Uncertain how much info should be exposed",    issue = "48043")]pub enum TryReserveErrorKind {    /// Error due to the computed capacity exceeding the collection's maximum    /// (usually `isize::MAX` bytes).    CapacityOverflow,     /// The memory allocator returned an error    AllocError {        /// The layout of allocation request that failed        layout: Layout,         #[doc(hidden)]        #[unstable(            feature = "container_error_extra",            issue = "none",            reason = "\            Enable exposing the allocator’s custom error value \            if an associated type is added in the future: \            https://github.com/rust-lang/wg-allocators/issues/23"        )]        non_exhaustive: (),    },} #[unstable(    feature = "try_reserve_kind",    reason = "Uncertain how much info should be exposed",    issue = "48043")]impl From<TryReserveErrorKind> for TryReserveError {    #[inline]    fn from(kind: TryReserveErrorKind) -> Self {        Self { kind }    }} #[unstable(feature = "try_reserve_kind", reason = "new API", issue = "48043")]impl From<LayoutError> for TryReserveErrorKind {    /// Always evaluates to [`TryReserveErrorKind::CapacityOverflow`].    #[inline]    fn from(_: LayoutError) -> Self {        TryReserveErrorKind::CapacityOverflow    }} #[stable(feature = "try_reserve", since = "1.57.0")]impl Display for TryReserveError {    fn fmt(        &self,        fmt: &mut core::fmt::Formatter<'_>,    ) -> core::result::Result<(), core::fmt::Error> {        fmt.write_str("memory allocation failed")?;        let reason = match self.kind {            TryReserveErrorKind::CapacityOverflow => {                " because the computed capacity exceeded the collection's maximum"            }            TryReserveErrorKind::AllocError { .. } => {                " because the memory allocator returned a error"            }        };        fmt.write_str(reason)    }} /// An intermediate trait for specialization of `Extend`.#[doc(hidden)]trait SpecExtend<I: IntoIterator> {    /// Extends `self` with the contents of the given iterator.    fn spec_extend(&mut self, iter: I);}