malachite_float/comparison/
hash.rs

1// Copyright © 2025 Mikhail Hogrefe
2//
3// This file is part of Malachite.
4//
5// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
6// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
7// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
8
9use crate::InnerFloat::{Finite, Infinity, NaN, Zero};
10use crate::{ComparableFloat, ComparableFloatRef, Float};
11use core::hash::{Hash, Hasher};
12
13impl Hash for ComparableFloat {
14    /// Computes a hash of a `ComparableFloat`.
15    ///
16    /// The hash is compatible with `ComparableFloat` equality: all `NaN`s hash to the same value.
17    ///
18    /// # Worst-case complexity
19    /// $T(n) = O(n)$
20    ///
21    /// $M(n) = O(1)$
22    ///
23    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.significant_bits()`.
24    #[inline]
25    fn hash<H: Hasher>(&self, state: &mut H) {
26        self.as_ref().hash(state);
27    }
28}
29
30impl Hash for ComparableFloatRef<'_> {
31    /// Computes a hash of a `ComparableFloatRef`.
32    ///
33    /// The hash is compatible with `ComparableFloatRef` equality: all `NaN`s hash to the same
34    /// value.
35    ///
36    /// # Worst-case complexity
37    /// $T(n) = O(n)$
38    ///
39    /// $M(n) = O(1)$
40    ///
41    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.significant_bits()`.
42    fn hash<H: Hasher>(&self, state: &mut H) {
43        match self.0 {
44            float_nan!() => "NaN".hash(state),
45            Float(Infinity { sign }) => {
46                if *sign {
47                    "Infinity".hash(state);
48                } else {
49                    "-Infinity".hash(state);
50                }
51            }
52            Float(Zero { sign }) => {
53                if *sign {
54                    "0.0".hash(state);
55                } else {
56                    "-0.0".hash(state);
57                }
58            }
59            Float(Finite {
60                sign,
61                exponent,
62                precision,
63                significand,
64            }) => {
65                sign.hash(state);
66                exponent.hash(state);
67                precision.hash(state);
68                significand.hash(state);
69            }
70        }
71    }
72}
malachite_float/comparison/hash.rs

malachite_float/comparison/
hash.rs
