1// SPDX-License-Identifier: Apache-2.0 OR MIT
  2
  3//! Collection types.
  4
  5#![stable(feature = "rust1", since = "1.0.0")]
  6
  7#[cfg(not(no_global_oom_handling))]
  8pub mod binary_heap;
  9#[cfg(not(no_global_oom_handling))]
 10mod btree;
 11#[cfg(not(no_global_oom_handling))]
 12pub mod linked_list;
 13#[cfg(not(no_global_oom_handling))]
 14pub mod vec_deque;
 15
 16#[cfg(not(no_global_oom_handling))]
 17#[stable(feature = "rust1", since = "1.0.0")]
 18pub mod btree_map {
 19    //! An ordered map based on a B-Tree.
 20    #[stable(feature = "rust1", since = "1.0.0")]
 21    pub use super::btree::map::*;
 22}
 23
 24#[cfg(not(no_global_oom_handling))]
 25#[stable(feature = "rust1", since = "1.0.0")]
 26pub mod btree_set {
 27    //! An ordered set based on a B-Tree.
 28    #[stable(feature = "rust1", since = "1.0.0")]
 29    pub use super::btree::set::*;
 30}
 31
 32#[cfg(not(no_global_oom_handling))]
 33#[stable(feature = "rust1", since = "1.0.0")]
 34#[doc(no_inline)]
 35pub use binary_heap::BinaryHeap;
 36
 37#[cfg(not(no_global_oom_handling))]
 38#[stable(feature = "rust1", since = "1.0.0")]
 39#[doc(no_inline)]
 40pub use btree_map::BTreeMap;
 41
 42#[cfg(not(no_global_oom_handling))]
 43#[stable(feature = "rust1", since = "1.0.0")]
 44#[doc(no_inline)]
 45pub use btree_set::BTreeSet;
 46
 47#[cfg(not(no_global_oom_handling))]
 48#[stable(feature = "rust1", since = "1.0.0")]
 49#[doc(no_inline)]
 50pub use linked_list::LinkedList;
 51
 52#[cfg(not(no_global_oom_handling))]
 53#[stable(feature = "rust1", since = "1.0.0")]
 54#[doc(no_inline)]
 55pub use vec_deque::VecDeque;
 56
 57use crate::alloc::{Layout, LayoutError};
 58use core::fmt::Display;
 59
 60/// The error type for `try_reserve` methods.
 61#[derive(Clone, PartialEq, Eq, Debug)]
 62#[stable(feature = "try_reserve", since = "1.57.0")]
 63pub struct TryReserveError {
 64    kind: TryReserveErrorKind,
 65}
 66
 67impl TryReserveError {
 68    /// Details about the allocation that caused the error
 69    #[inline]
 70    #[must_use]
 71    #[unstable(
 72        feature = "try_reserve_kind",
 73        reason = "Uncertain how much info should be exposed",
 74        issue = "48043"
 75    )]
 76    pub fn kind(&self) -> TryReserveErrorKind {
 77        self.kind.clone()
 78    }
 79}
 80
 81/// Details of the allocation that caused a `TryReserveError`
 82#[derive(Clone, PartialEq, Eq, Debug)]
 83#[unstable(
 84    feature = "try_reserve_kind",
 85    reason = "Uncertain how much info should be exposed",
 86    issue = "48043"
 87)]
 88pub enum TryReserveErrorKind {
 89    /// Error due to the computed capacity exceeding the collection's maximum
 90    /// (usually `isize::MAX` bytes).
 91    CapacityOverflow,
 92
 93    /// The memory allocator returned an error
 94    AllocError {
 95        /// The layout of allocation request that failed
 96        layout: Layout,
 97
 98        #[doc(hidden)]
 99        #[unstable(
100            feature = "container_error_extra",
101            issue = "none",
102            reason = "\
103            Enable exposing the allocator’s custom error value \
104            if an associated type is added in the future: \
105            https://github.com/rust-lang/wg-allocators/issues/23"
106        )]
107        non_exhaustive: (),
108    },
109}
110
111#[unstable(
112    feature = "try_reserve_kind",
113    reason = "Uncertain how much info should be exposed",
114    issue = "48043"
115)]
116impl From<TryReserveErrorKind> for TryReserveError {
117    #[inline]
118    fn from(kind: TryReserveErrorKind) -> Self {
119        Self { kind }
120    }
121}
122
123#[unstable(feature = "try_reserve_kind", reason = "new API", issue = "48043")]
124impl From<LayoutError> for TryReserveErrorKind {
125    /// Always evaluates to [`TryReserveErrorKind::CapacityOverflow`].
126    #[inline]
127    fn from(_: LayoutError) -> Self {
128        TryReserveErrorKind::CapacityOverflow
129    }
130}
131
132#[stable(feature = "try_reserve", since = "1.57.0")]
133impl Display for TryReserveError {
134    fn fmt(
135        &self,
136        fmt: &mut core::fmt::Formatter<'_>,
137    ) -> core::result::Result<(), core::fmt::Error> {
138        fmt.write_str("memory allocation failed")?;
139        let reason = match self.kind {
140            TryReserveErrorKind::CapacityOverflow => {
141                " because the computed capacity exceeded the collection's maximum"
142            }
143            TryReserveErrorKind::AllocError { .. } => {
144                " because the memory allocator returned an error"
145            }
146        };
147        fmt.write_str(reason)
148    }
149}
150
151/// An intermediate trait for specialization of `Extend`.
152#[doc(hidden)]
153trait SpecExtend<I: IntoIterator> {
154    /// Extends `self` with the contents of the given iterator.
155    fn spec_extend(&mut self, iter: I);
156}
157
158#[stable(feature = "try_reserve", since = "1.57.0")]
159impl core::error::Error for TryReserveError {}