/rust/registry/src/index.crates.io-1949cf8c6b5b557f/indexmap-2.11.4/src/lib.rs

Source
// We *mostly* avoid unsafe code, but `Slice` allows it for DST casting.
#![deny(unsafe_code)]
#![warn(rust_2018_idioms)]
#![no_std]

//! [`IndexMap`] is a hash table where the iteration order of the key-value
//! pairs is independent of the hash values of the keys.
//!
//! [`IndexSet`] is a corresponding hash set using the same implementation and
//! with similar properties.
//!
//! ### Highlights
//!
//! [`IndexMap`] and [`IndexSet`] are drop-in compatible with the std `HashMap`
//! and `HashSet`, but they also have some features of note:
//!
//! - The ordering semantics (see their documentation for details)
//! - Sorting methods and the [`.pop()`][IndexMap::pop] methods.
//! - The [`Equivalent`] trait, which offers more flexible equality definitions
//!   between borrowed and owned versions of keys.
//! - The [`MutableKeys`][map::MutableKeys] trait, which gives opt-in mutable
//!   access to map keys, and [`MutableValues`][set::MutableValues] for sets.
//!
//! ### Feature Flags
//!
//! To reduce the amount of compiled code in the crate by default, certain
//! features are gated behind [feature flags]. These allow you to opt in to (or
//! out of) functionality. Below is a list of the features available in this
//! crate.
//!
//! * `std`: Enables features which require the Rust standard library. For more
//!   information see the section on [`no_std`].
//! * `rayon`: Enables parallel iteration and other parallel methods.
//! * `serde`: Adds implementations for [`Serialize`] and [`Deserialize`]
//!   to [`IndexMap`] and [`IndexSet`]. Alternative implementations for
//!   (de)serializing [`IndexMap`] as an ordered sequence are available in the
//!   [`map::serde_seq`] module.
//! * `arbitrary`: Adds implementations for the [`arbitrary::Arbitrary`] trait
//!   to [`IndexMap`] and [`IndexSet`].
//! * `quickcheck`: Adds implementations for the [`quickcheck::Arbitrary`] trait
//!   to [`IndexMap`] and [`IndexSet`].
//! * `borsh` (**deprecated**): Adds implementations for [`BorshSerialize`] and
//!   [`BorshDeserialize`] to [`IndexMap`] and [`IndexSet`]. Due to a cyclic
//!   dependency that arose between [`borsh`] and `indexmap`, `borsh v1.5.6`
//!   added an `indexmap` feature that should be used instead of enabling the
//!   feature here.
//!
//! _Note: only the `std` feature is enabled by default._
//!
//! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section
//! [`no_std`]: #no-standard-library-targets
//! [`Serialize`]: `::serde_core::Serialize`
//! [`Deserialize`]: `::serde_core::Deserialize`
//! [`BorshSerialize`]: `::borsh::BorshSerialize`
//! [`BorshDeserialize`]: `::borsh::BorshDeserialize`
//! [`borsh`]: `::borsh`
//! [`arbitrary::Arbitrary`]: `::arbitrary::Arbitrary`
//! [`quickcheck::Arbitrary`]: `::quickcheck::Arbitrary`
//!
//! ### Alternate Hashers
//!
//! [`IndexMap`] and [`IndexSet`] have a default hasher type
//! [`S = RandomState`][std::collections::hash_map::RandomState],
//! just like the standard `HashMap` and `HashSet`, which is resistant to
//! HashDoS attacks but not the most performant. Type aliases can make it easier
//! to use alternate hashers:
//!
//! ```
//! use fnv::FnvBuildHasher;
//! use indexmap::{IndexMap, IndexSet};
//!
//! type FnvIndexMap<K, V> = IndexMap<K, V, FnvBuildHasher>;
//! type FnvIndexSet<T> = IndexSet<T, FnvBuildHasher>;
//!
//! let std: IndexSet<i32> = (0..100).collect();
//! let fnv: FnvIndexSet<i32> = (0..100).collect();
//! assert_eq!(std, fnv);
//! ```
//!
//! ### Rust Version
//!
//! This version of indexmap requires Rust 1.63 or later.
//!
//! The indexmap 2.x release series will use a carefully considered version
//! upgrade policy, where in a later 2.x version, we will raise the minimum
//! required Rust version.
//!
//! ## No Standard Library Targets
//!
//! This crate supports being built without `std`, requiring `alloc` instead.
//! This is chosen by disabling the default "std" cargo feature, by adding
//! `default-features = false` to your dependency specification.
//!
//! - Creating maps and sets using [`new`][IndexMap::new] and
//!   [`with_capacity`][IndexMap::with_capacity] is unavailable without `std`.
//!   Use methods [`IndexMap::default`], [`with_hasher`][IndexMap::with_hasher],
//!   [`with_capacity_and_hasher`][IndexMap::with_capacity_and_hasher] instead.
//!   A no-std compatible hasher will be needed as well, for example
//!   from the crate `twox-hash`.
//! - Macros [`indexmap!`] and [`indexset!`] are unavailable without `std`. Use
//!   the macros [`indexmap_with_default!`] and [`indexset_with_default!`] instead.

#![cfg_attr(docsrs, feature(doc_cfg))]

extern crate alloc;

#[cfg(feature = "std")]
#[macro_use]
extern crate std;

mod arbitrary;
#[macro_use]
mod macros;
#[cfg(feature = "borsh")]
mod borsh;
#[cfg(feature = "serde")]
mod serde;
#[cfg(feature = "sval")]
mod sval;
mod util;

pub mod map;
pub mod set;

// Placed after `map` and `set` so new `rayon` methods on the types
// are documented after the "normal" methods.
#[cfg(feature = "rayon")]
mod rayon;

pub use crate::map::IndexMap;
pub use crate::set::IndexSet;
pub use equivalent::Equivalent;

// shared private items

/// Hash value newtype. Not larger than usize, since anything larger
/// isn't used for selecting position anyway.
#[derive(Clone, Copy, Debug, PartialEq)]
struct HashValue(usize);

impl HashValue {
    #[inline(always)]
    fn get(self) -> u64 {
        self.0 as u64
    }
}

#[derive(Copy, Debug)]
struct Bucket<K, V> {
    hash: HashValue,
    key: K,
    value: V,
}

impl<K, V> Clone for Bucket<K, V>
where
    K: Clone,
    V: Clone,
{
    fn clone(&self) -> Self {
        Bucket {
            hash: self.hash,
            key: self.key.clone(),
            value: self.value.clone(),
        }
    }

    fn clone_from(&mut self, other: &Self) {
        self.hash = other.hash;
        self.key.clone_from(&other.key);
        self.value.clone_from(&other.value);
    }
}

impl<K, V> Bucket<K, V> {
    // field accessors -- used for `f` instead of closures in `.map(f)`
    fn key_ref(&self) -> &K {
        &self.key
    }
    fn value_ref(&self) -> &V {
        &self.value
    }
    fn value_mut(&mut self) -> &mut V {
        &mut self.value
    }
    fn key(self) -> K {
        self.key
    }
    fn value(self) -> V {
        self.value
    }
    fn key_value(self) -> (K, V) {
        (self.key, self.value)
    }
    fn refs(&self) -> (&K, &V) {
        (&self.key, &self.value)
    }
    fn ref_mut(&mut self) -> (&K, &mut V) {
        (&self.key, &mut self.value)
    }
    fn muts(&mut self) -> (&mut K, &mut V) {
        (&mut self.key, &mut self.value)
    }
}

/// The error type for [`try_reserve`][IndexMap::try_reserve] methods.
#[derive(Clone, PartialEq, Eq, Debug)]
pub struct TryReserveError {
    kind: TryReserveErrorKind,
}

#[derive(Clone, PartialEq, Eq, Debug)]
enum TryReserveErrorKind {
    // The standard library's kind is currently opaque to us, otherwise we could unify this.
    Std(alloc::collections::TryReserveError),
    CapacityOverflow,
    AllocError { layout: alloc::alloc::Layout },
}

// These are not `From` so we don't expose them in our public API.
impl TryReserveError {
    fn from_alloc(error: alloc::collections::TryReserveError) -> Self {
        Self {
            kind: TryReserveErrorKind::Std(error),
        }
    }

    fn from_hashbrown(error: hashbrown::TryReserveError) -> Self {
        Self {
            kind: match error {
                hashbrown::TryReserveError::CapacityOverflow => {
                    TryReserveErrorKind::CapacityOverflow
                }
                hashbrown::TryReserveError::AllocError { layout } => {
                    TryReserveErrorKind::AllocError { layout }
                }
            },
        }
    }
}

impl core::fmt::Display for TryReserveError {
    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
        let reason = match &self.kind {
            TryReserveErrorKind::Std(e) => return core::fmt::Display::fmt(e, f),
            TryReserveErrorKind::CapacityOverflow => {
                " because the computed capacity exceeded the collection's maximum"
            }
            TryReserveErrorKind::AllocError { .. } => {
                " because the memory allocator returned an error"
            }
        };
        f.write_str("memory allocation failed")?;
        f.write_str(reason)
    }
}

#[cfg(feature = "std")]
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
impl std::error::Error for TryReserveError {}

// NOTE: This is copied from the slice module in the std lib.
/// The error type returned by [`get_disjoint_indices_mut`][`IndexMap::get_disjoint_indices_mut`].
///
/// It indicates one of two possible errors:
/// - An index is out-of-bounds.
/// - The same index appeared multiple times in the array.
//    (or different but overlapping indices when ranges are provided)
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum GetDisjointMutError {
    /// An index provided was out-of-bounds for the slice.
    IndexOutOfBounds,
    /// Two indices provided were overlapping.
    OverlappingIndices,
}

impl core::fmt::Display for GetDisjointMutError {
    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
        let msg = match self {
            GetDisjointMutError::IndexOutOfBounds => "an index is out of bounds",
            GetDisjointMutError::OverlappingIndices => "there were overlapping indices",
        };

        core::fmt::Display::fmt(msg, f)
    }
}

#[cfg(feature = "std")]
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
impl std::error::Error for GetDisjointMutError {}

Coverage Report

Created: 2026-05-18 06:32

Line	Count	Source
1		// We mostly avoid unsafe code, but `Slice` allows it for DST casting.
2		#![deny(unsafe_code)]
3		#![warn(rust_2018_idioms)]
4		#![no_std]
5
6		//! [`IndexMap`] is a hash table where the iteration order of the key-value
7		//! pairs is independent of the hash values of the keys.
8		//!
9		//! [`IndexSet`] is a corresponding hash set using the same implementation and
10		//! with similar properties.
11		//!
12		//! ### Highlights
13		//!
14		//! [`IndexMap`] and [`IndexSet`] are drop-in compatible with the std `HashMap`
15		//! and `HashSet`, but they also have some features of note:
16		//!
17		//! - The ordering semantics (see their documentation for details)
18		//! - Sorting methods and the [`.pop()`][IndexMap::pop] methods.
19		//! - The [`Equivalent`] trait, which offers more flexible equality definitions
20		//! between borrowed and owned versions of keys.
21		//! - The [`MutableKeys`][map::MutableKeys] trait, which gives opt-in mutable
22		//! access to map keys, and [`MutableValues`][set::MutableValues] for sets.
23		//!
24		//! ### Feature Flags
25		//!
26		//! To reduce the amount of compiled code in the crate by default, certain
27		//! features are gated behind [feature flags]. These allow you to opt in to (or
28		//! out of) functionality. Below is a list of the features available in this
29		//! crate.
30		//!
31		//! * `std`: Enables features which require the Rust standard library. For more
32		//! information see the section on [`no_std`].
33		//! * `rayon`: Enables parallel iteration and other parallel methods.
34		//! * `serde`: Adds implementations for [`Serialize`] and [`Deserialize`]
35		//! to [`IndexMap`] and [`IndexSet`]. Alternative implementations for
36		//! (de)serializing [`IndexMap`] as an ordered sequence are available in the
37		//! [`map::serde_seq`] module.
38		//! * `arbitrary`: Adds implementations for the [`arbitrary::Arbitrary`] trait
39		//! to [`IndexMap`] and [`IndexSet`].
40		//! * `quickcheck`: Adds implementations for the [`quickcheck::Arbitrary`] trait
41		//! to [`IndexMap`] and [`IndexSet`].
42		//! * `borsh` (deprecated): Adds implementations for [`BorshSerialize`] and
43		//! [`BorshDeserialize`] to [`IndexMap`] and [`IndexSet`]. Due to a cyclic
44		//! dependency that arose between [`borsh`] and `indexmap`, `borsh v1.5.6`
45		//! added an `indexmap` feature that should be used instead of enabling the
46		//! feature here.
47		//!
48		//! _Note: only the `std` feature is enabled by default._
49		//!
50		//! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section
51		//! [`no_std`]: #no-standard-library-targets
52		//! [`Serialize`]: `::serde_core::Serialize`
53		//! [`Deserialize`]: `::serde_core::Deserialize`
54		//! [`BorshSerialize`]: `::borsh::BorshSerialize`
55		//! [`BorshDeserialize`]: `::borsh::BorshDeserialize`
56		//! [`borsh`]: `::borsh`
57		//! [`arbitrary::Arbitrary`]: `::arbitrary::Arbitrary`
58		//! [`quickcheck::Arbitrary`]: `::quickcheck::Arbitrary`
59		//!
60		//! ### Alternate Hashers
61		//!
62		//! [`IndexMap`] and [`IndexSet`] have a default hasher type
63		//! [`S = RandomState`][std::collections::hash_map::RandomState],
64		//! just like the standard `HashMap` and `HashSet`, which is resistant to
65		//! HashDoS attacks but not the most performant. Type aliases can make it easier
66		//! to use alternate hashers:
67		//!
68		//! ```
69		//! use fnv::FnvBuildHasher;
70		//! use indexmap::{IndexMap, IndexSet};
71		//!
72		//! type FnvIndexMap<K, V> = IndexMap<K, V, FnvBuildHasher>;
73		//! type FnvIndexSet<T> = IndexSet<T, FnvBuildHasher>;
74		//!
75		//! let std: IndexSet<i32> = (0..100).collect();
76		//! let fnv: FnvIndexSet<i32> = (0..100).collect();
77		//! assert_eq!(std, fnv);
78		//! ```
79		//!
80		//! ### Rust Version
81		//!
82		//! This version of indexmap requires Rust 1.63 or later.
83		//!
84		//! The indexmap 2.x release series will use a carefully considered version
85		//! upgrade policy, where in a later 2.x version, we will raise the minimum
86		//! required Rust version.
87		//!
88		//! ## No Standard Library Targets
89		//!
90		//! This crate supports being built without `std`, requiring `alloc` instead.
91		//! This is chosen by disabling the default "std" cargo feature, by adding
92		//! `default-features = false` to your dependency specification.
93		//!
94		//! - Creating maps and sets using [`new`][IndexMap::new] and
95		//! [`with_capacity`][IndexMap::with_capacity] is unavailable without `std`.
96		//! Use methods [`IndexMap::default`], [`with_hasher`][IndexMap::with_hasher],
97		//! [`with_capacity_and_hasher`][IndexMap::with_capacity_and_hasher] instead.
98		//! A no-std compatible hasher will be needed as well, for example
99		//! from the crate `twox-hash`.
100		//! - Macros [`indexmap!`] and [`indexset!`] are unavailable without `std`. Use
101		//! the macros [`indexmap_with_default!`] and [`indexset_with_default!`] instead.
102
103		#![cfg_attr(docsrs, feature(doc_cfg))]
104
105		extern crate alloc;
106
107		#[cfg(feature = "std")]
108		#[macro_use]
109		extern crate std;
110
111		mod arbitrary;
112		#[macro_use]
113		mod macros;
114		#[cfg(feature = "borsh")]
115		mod borsh;
116		#[cfg(feature = "serde")]
117		mod serde;
118		#[cfg(feature = "sval")]
119		mod sval;
120		mod util;
121
122		pub mod map;
123		pub mod set;
124
125		// Placed after `map` and `set` so new `rayon` methods on the types
126		// are documented after the "normal" methods.
127		#[cfg(feature = "rayon")]
128		mod rayon;
129
130		pub use crate::map::IndexMap;
131		pub use crate::set::IndexSet;
132		pub use equivalent::Equivalent;
133
134		// shared private items
135
136		/// Hash value newtype. Not larger than usize, since anything larger
137		/// isn't used for selecting position anyway.
138		#[derive(Clone, Copy, Debug, PartialEq)]
139		struct HashValue(usize);
140
141		impl HashValue {
142		#[inline(always)]
143	5.87M	fn get(self) -> u64 {
144	5.87M	self.0 as u64
145	5.87M	}
146		}
147
148		#[derive(Copy, Debug)]
149		struct Bucket<K, V> {
150		hash: HashValue,
151		key: K,
152		value: V,
153		}
154
155		impl<K, V> Clone for Bucket<K, V>
156		where
157		K: Clone,
158		V: Clone,
159		{
160		fn clone(&self) -> Self {
161		Bucket {
162		hash: self.hash,
163		key: self.key.clone(),
164		value: self.value.clone(),
165		}
166		}
167
168		fn clone_from(&mut self, other: &Self) {
169		self.hash = other.hash;
170		self.key.clone_from(&other.key);
171		self.value.clone_from(&other.value);
172		}
173		}
174
175		impl<K, V> Bucket<K, V> {
176		// field accessors -- used for `f` instead of closures in `.map(f)`
177		fn key_ref(&self) -> &K {
178		&self.key
179		}
180		fn value_ref(&self) -> &V {
181		&self.value
182		}
183	0	fn value_mut(&mut self) -> &mut V {
184	0	&mut self.value
185	0	} Unexecuted instantiation: <indexmap::Bucket<neqo_transport::stream_id::StreamId, neqo_transport::send_stream::SendStream>>::value_mut Unexecuted instantiation: <indexmap::Bucket<alloc::string::String, serde_json::value::Value>>::value_mut
186		fn key(self) -> K {
187		self.key
188		}
189		fn value(self) -> V {
190		self.value
191		}
192		fn key_value(self) -> (K, V) {
193		(self.key, self.value)
194		}
195	0	fn refs(&self) -> (&K, &V) {
196	0	(&self.key, &self.value)
197	0	} Unexecuted instantiation: <indexmap::Bucket<sfv::key::Key, sfv::GenericBareItem<sfv::string::String, alloc::vec::Vec<u8>, sfv::token::Token, alloc::string::String>>>::refs Unexecuted instantiation: <indexmap::Bucket<sfv::key::Key, sfv::parsed::ListEntry>>::refs Unexecuted instantiation: <indexmap::Bucket<alloc::string::String, serde_json::value::Value>>::refs Unexecuted instantiation: <indexmap::Bucket<alloc::string::String, serde_json::value::Value>>::refs
198	0	fn ref_mut(&mut self) -> (&K, &mut V) {
199	0	(&self.key, &mut self.value)
200	0	}
201		fn muts(&mut self) -> (&mut K, &mut V) {
202		(&mut self.key, &mut self.value)
203		}
204		}
205
206		/// The error type for [`try_reserve`][IndexMap::try_reserve] methods.
207		#[derive(Clone, PartialEq, Eq, Debug)]
208		pub struct TryReserveError {
209		kind: TryReserveErrorKind,
210		}
211
212		#[derive(Clone, PartialEq, Eq, Debug)]
213		enum TryReserveErrorKind {
214		// The standard library's kind is currently opaque to us, otherwise we could unify this.
215		Std(alloc::collections::TryReserveError),
216		CapacityOverflow,
217		AllocError { layout: alloc::alloc::Layout },
218		}
219
220		// These are not `From` so we don't expose them in our public API.
221		impl TryReserveError {
222		fn from_alloc(error: alloc::collections::TryReserveError) -> Self {
223		Self {
224		kind: TryReserveErrorKind::Std(error),
225		}
226		}
227
228		fn from_hashbrown(error: hashbrown::TryReserveError) -> Self {
229		Self {
230		kind: match error {
231		hashbrown::TryReserveError::CapacityOverflow => {
232		TryReserveErrorKind::CapacityOverflow
233		}
234		hashbrown::TryReserveError::AllocError { layout } => {
235		TryReserveErrorKind::AllocError { layout }
236		}
237		},
238		}
239		}
240		}
241
242		impl core::fmt::Display for TryReserveError {
243		fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
244		let reason = match &self.kind {
245		TryReserveErrorKind::Std(e) => return core::fmt::Display::fmt(e, f),
246		TryReserveErrorKind::CapacityOverflow => {
247		" because the computed capacity exceeded the collection's maximum"
248		}
249		TryReserveErrorKind::AllocError { .. } => {
250		" because the memory allocator returned an error"
251		}
252		};
253		f.write_str("memory allocation failed")?;
254		f.write_str(reason)
255		}
256		}
257
258		#[cfg(feature = "std")]
259		#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
260		impl std::error::Error for TryReserveError {}
261
262		// NOTE: This is copied from the slice module in the std lib.
263		/// The error type returned by [`get_disjoint_indices_mut`][`IndexMap::get_disjoint_indices_mut`].
264		///
265		/// It indicates one of two possible errors:
266		/// - An index is out-of-bounds.
267		/// - The same index appeared multiple times in the array.
268		// (or different but overlapping indices when ranges are provided)
269		#[derive(Debug, Clone, PartialEq, Eq)]
270		pub enum GetDisjointMutError {
271		/// An index provided was out-of-bounds for the slice.
272		IndexOutOfBounds,
273		/// Two indices provided were overlapping.
274		OverlappingIndices,
275		}
276
277		impl core::fmt::Display for GetDisjointMutError {
278		fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
279		let msg = match self {
280		GetDisjointMutError::IndexOutOfBounds => "an index is out of bounds",
281		GetDisjointMutError::OverlappingIndices => "there were overlapping indices",
282		};
283
284		core::fmt::Display::fmt(msg, f)
285		}
286		}
287
288		#[cfg(feature = "std")]
289		#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
290		impl std::error::Error for GetDisjointMutError {}