kempt/
lib.rs

1#![doc = include_str!("../README.md")]
2#![no_std]
3#![forbid(unsafe_code)]
4#![warn(missing_docs, clippy::pedantic)]
5
6use alloc::string::String;
7use alloc::vec::Vec;
8use core::cmp::Ordering;
9
10#[cfg(test)]
11extern crate std;
12
13extern crate alloc;
14
15/// Types supporting the [`Map<Key, Value>`] collection type.
16pub mod map;
17/// Types supporting the [`Set<T>`] collection type.
18pub mod set;
19
20pub use map::Map;
21pub use set::Set;
22
23#[cfg(feature = "serde")]
24mod serde;
25
26#[cfg(test)]
27mod tests;
28
29/// Provides a comparison between `Self` and `Other`.
30///
31/// This function should only be implemented for types who guarantee that their
32/// `PartialOrd<Other>` implementations are identical to their `PartialOrd`
33/// implementations. For example, `Path` and `PathBuf` can be interchangeably
34/// compared regardless of whether the left or right or both are a `Path` or
35/// `PathBuf`.
36///
37/// Why not just use `PartialOrd<Other>`? Unfortunately, `PartialOrd<str>` is
38/// [not implemented for
39/// `String`](https://github.com/rust-lang/rust/issues/82990). This led to
40/// issues implementing the [`Map::entry`] function when passing a `&str`
41/// when the `Key` type was `String`.
42///
43/// This trait is automatically implemented for types that implement `Ord` and
44/// `PartialOrd<Other>`, but it additionally provides implementations for
45/// `String`/`str` and `Vec<T>`/`[T]`.
46///
47/// **In general, this trait should not need to be implemented.** Implement
48/// `Ord` on your `Key` type, and if needed, implement `PartialOrd<Other>` for
49/// your borrowed form.
50pub trait Sort<Other = Self>
51where
52    Other: ?Sized,
53{
54    /// Compare `self` and `other`, returning the comparison result.
55    ///
56    /// This function should be implemented identically to
57    /// `Ord::cmp`/`PartialOrd::partial_cmp`.
58    fn compare(&self, other: &Other) -> Ordering;
59}
60
61impl Sort<str> for String {
62    #[inline]
63    fn compare(&self, b: &str) -> Ordering {
64        self.as_str().cmp(b)
65    }
66}
67
68impl<T> Sort<[T]> for Vec<T>
69where
70    T: Ord,
71{
72    #[inline]
73    fn compare(&self, b: &[T]) -> Ordering {
74        self.as_slice().cmp(b)
75    }
76}
77
78impl<Key, SearchFor> Sort<SearchFor> for Key
79where
80    Key: Ord + PartialOrd<SearchFor>,
81{
82    #[inline]
83    fn compare(&self, b: &SearchFor) -> Ordering {
84        self.partial_cmp(b).expect("comparison failed")
85    }
86}
kempt/lib.rs

kempt/
lib.rs
