hashbrown/
lib.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
//! This crate is a Rust port of Google's high-performance [SwissTable] hash
//! map, adapted to make it a drop-in replacement for Rust's standard `HashMap`
//! and `HashSet` types.
//!
//! The original C++ version of [SwissTable] can be found [here], and this
//! [CppCon talk] gives an overview of how the algorithm works.
//!
//! [SwissTable]: https://abseil.io/blog/20180927-swisstables
//! [here]: https://github.com/abseil/abseil-cpp/blob/master/absl/container/internal/raw_hash_set.h
//! [CppCon talk]: https://www.youtube.com/watch?v=ncHmEUmJZf4

#![no_std]
#![cfg_attr(
    feature = "nightly",
    feature(
        test,
        core_intrinsics,
        dropck_eyepatch,
        min_specialization,
        extend_one,
        allocator_api,
        slice_ptr_get,
        maybe_uninit_array_assume_init,
        strict_provenance_lints
    )
)]
#![cfg_attr(feature = "rustc-dep-of-std", feature(rustc_attrs))]
#![allow(
    clippy::doc_markdown,
    clippy::module_name_repetitions,
    clippy::must_use_candidate,
    clippy::option_if_let_else,
    clippy::redundant_else,
    clippy::manual_map,
    clippy::missing_safety_doc,
    clippy::missing_errors_doc
)]
#![warn(missing_docs)]
#![warn(rust_2018_idioms)]
#![cfg_attr(feature = "nightly", warn(fuzzy_provenance_casts))]
#![cfg_attr(feature = "nightly", allow(internal_features))]

/// Default hasher for [`HashMap`] and [`HashSet`].
#[cfg(feature = "default-hasher")]
pub type DefaultHashBuilder = foldhash::fast::RandomState;

/// Dummy default hasher for [`HashMap`] and [`HashSet`].
#[cfg(not(feature = "default-hasher"))]
pub enum DefaultHashBuilder {}

#[cfg(test)]
#[macro_use]
extern crate std;

#[cfg_attr(test, macro_use)]
#[cfg_attr(feature = "rustc-dep-of-std", allow(unused_extern_crates))]
extern crate alloc;

#[cfg(feature = "nightly")]
#[cfg(doctest)]
doc_comment::doctest!("../README.md");

#[macro_use]
mod macros;

mod control;
mod raw;
mod util;

mod external_trait_impls;
mod map;
#[cfg(feature = "raw-entry")]
mod raw_entry;
#[cfg(feature = "rustc-internal-api")]
mod rustc_entry;
mod scopeguard;
mod set;
mod table;

pub mod hash_map {
    //! A hash map implemented with quadratic probing and SIMD lookup.
    pub use crate::map::*;

    #[cfg(feature = "rustc-internal-api")]
    pub use crate::rustc_entry::*;

    #[cfg(feature = "rayon")]
    /// [rayon]-based parallel iterator types for hash maps.
    /// You will rarely need to interact with it directly unless you have need
    /// to name one of the iterator types.
    ///
    /// [rayon]: https://docs.rs/rayon/1.0/rayon
    pub mod rayon {
        pub use crate::external_trait_impls::rayon::map::*;
    }
}
pub mod hash_set {
    //! A hash set implemented as a `HashMap` where the value is `()`.
    pub use crate::set::*;

    #[cfg(feature = "rayon")]
    /// [rayon]-based parallel iterator types for hash sets.
    /// You will rarely need to interact with it directly unless you have need
    /// to name one of the iterator types.
    ///
    /// [rayon]: https://docs.rs/rayon/1.0/rayon
    pub mod rayon {
        pub use crate::external_trait_impls::rayon::set::*;
    }
}
pub mod hash_table {
    //! A hash table implemented with quadratic probing and SIMD lookup.
    pub use crate::table::*;

    #[cfg(feature = "rayon")]
    /// [rayon]-based parallel iterator types for hash tables.
    /// You will rarely need to interact with it directly unless you have need
    /// to name one of the iterator types.
    ///
    /// [rayon]: https://docs.rs/rayon/1.0/rayon
    pub mod rayon {
        pub use crate::external_trait_impls::rayon::table::*;
    }
}

pub use crate::map::HashMap;
pub use crate::set::HashSet;
pub use crate::table::HashTable;

#[cfg(feature = "equivalent")]
pub use equivalent::Equivalent;

// This is only used as a fallback when building as part of `std`.
#[cfg(not(feature = "equivalent"))]
/// Key equivalence trait.
///
/// This trait defines the function used to compare the input value with the
/// map keys (or set values) during a lookup operation such as [`HashMap::get`]
/// or [`HashSet::contains`].
/// It is provided with a blanket implementation based on the
/// [`Borrow`](core::borrow::Borrow) trait.
///
/// # Correctness
///
/// Equivalent values must hash to the same value.
pub trait Equivalent<K: ?Sized> {
    /// Checks if this value is equivalent to the given key.
    ///
    /// Returns `true` if both values are equivalent, and `false` otherwise.
    ///
    /// # Correctness
    ///
    /// When this function returns `true`, both `self` and `key` must hash to
    /// the same value.
    fn equivalent(&self, key: &K) -> bool;
}

#[cfg(not(feature = "equivalent"))]
impl<Q: ?Sized, K: ?Sized> Equivalent<K> for Q
where
    Q: Eq,
    K: core::borrow::Borrow<Q>,
{
    fn equivalent(&self, key: &K) -> bool {
        self == key.borrow()
    }
}

/// The error type for `try_reserve` methods.
#[derive(Clone, PartialEq, Eq, Debug)]
pub enum TryReserveError {
    /// 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 the allocation request that failed.
        layout: alloc::alloc::Layout,
    },
}