-
Notifications
You must be signed in to change notification settings - Fork 12.8k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Move RandomState and DefaultHasher into std::hash, but in a sneaky way
- Loading branch information
1 parent
b0b8c52
commit e9b83cf
Showing
9 changed files
with
262 additions
and
157 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,90 @@ | ||
| //! Generic hashing support. | ||
| //! | ||
| //! This module provides a generic way to compute the [hash] of a value. | ||
| //! Hashes are most commonly used with [`HashMap`] and [`HashSet`]. | ||
| //! | ||
| //! [hash]: https://en.wikipedia.org/wiki/Hash_function | ||
| //! [`HashMap`]: ../../std/collections/struct.HashMap.html | ||
| //! [`HashSet`]: ../../std/collections/struct.HashSet.html | ||
| //! | ||
| //! The simplest way to make a type hashable is to use `#[derive(Hash)]`: | ||
| //! | ||
| //! # Examples | ||
| //! | ||
| //! ```rust | ||
| //! use std::collections::hash_map::DefaultHasher; | ||
| //! use std::hash::{Hash, Hasher}; | ||
| //! | ||
| //! #[derive(Hash)] | ||
| //! struct Person { | ||
| //! id: u32, | ||
| //! name: String, | ||
| //! phone: u64, | ||
| //! } | ||
| //! | ||
| //! let person1 = Person { | ||
| //! id: 5, | ||
| //! name: "Janet".to_string(), | ||
| //! phone: 555_666_7777, | ||
| //! }; | ||
| //! let person2 = Person { | ||
| //! id: 5, | ||
| //! name: "Bob".to_string(), | ||
| //! phone: 555_666_7777, | ||
| //! }; | ||
| //! | ||
| //! assert!(calculate_hash(&person1) != calculate_hash(&person2)); | ||
| //! | ||
| //! fn calculate_hash<T: Hash>(t: &T) -> u64 { | ||
| //! let mut s = DefaultHasher::new(); | ||
| //! t.hash(&mut s); | ||
| //! s.finish() | ||
| //! } | ||
| //! ``` | ||
| //! | ||
| //! If you need more control over how a value is hashed, you need to implement | ||
| //! the [`Hash`] trait: | ||
| //! | ||
| //! ```rust | ||
| //! use std::collections::hash_map::DefaultHasher; | ||
| //! use std::hash::{Hash, Hasher}; | ||
| //! | ||
| //! struct Person { | ||
| //! id: u32, | ||
| //! # #[allow(dead_code)] | ||
| //! name: String, | ||
| //! phone: u64, | ||
| //! } | ||
| //! | ||
| //! impl Hash for Person { | ||
| //! fn hash<H: Hasher>(&self, state: &mut H) { | ||
| //! self.id.hash(state); | ||
| //! self.phone.hash(state); | ||
| //! } | ||
| //! } | ||
| //! | ||
| //! let person1 = Person { | ||
| //! id: 5, | ||
| //! name: "Janet".to_string(), | ||
| //! phone: 555_666_7777, | ||
| //! }; | ||
| //! let person2 = Person { | ||
| //! id: 5, | ||
| //! name: "Bob".to_string(), | ||
| //! phone: 555_666_7777, | ||
| //! }; | ||
| //! | ||
| //! assert_eq!(calculate_hash(&person1), calculate_hash(&person2)); | ||
| //! | ||
| //! fn calculate_hash<T: Hash>(t: &T) -> u64 { | ||
| //! let mut s = DefaultHasher::new(); | ||
| //! t.hash(&mut s); | ||
| //! s.finish() | ||
| //! } | ||
| //! ``` | ||
| #![stable(feature = "rust1", since = "1.0.0")] | ||
|
|
||
| pub(crate) mod private; | ||
|
|
||
| #[stable(feature = "rust1", since = "1.0.0")] | ||
| pub use core::hash::*; |
Oops, something went wrong.