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malachite_nz/integer_polynomial/comparison/
partial_eq_integer.rs

1// Copyright © 2026 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::integer::Integer;
10use crate::integer_polynomial::IntegerPolynomial;
11
12impl PartialEq<Integer> for IntegerPolynomial {
13    /// Determines whether an [`IntegerPolynomial`] is equal to an [`Integer`].
14    ///
15    /// The polynomial is equal to the [`Integer`] when it is the constant polynomial with that
16    /// value, so the zero polynomial is equal to 0 and nothing else, and no polynomial of positive
17    /// degree is equal to any [`Integer`].
18    ///
19    /// # Worst-case complexity
20    /// $T(n) = O(n)$
21    ///
22    /// $M(n) = O(1)$
23    ///
24    /// where $T$ is time, $M$ is additional memory, and $n$ is
25    /// `min(self.coefficient(0).significant_bits(), other.significant_bits())`.
26    ///
27    /// # Examples
28    /// See [here](super::partial_eq_integer#partial_eq).
29    fn eq(&self, other: &Integer) -> bool {
30        match self.coefficients.as_slice() {
31            [] => *other == 0u32,
32            [c] => c == other,
33            _ => false,
34        }
35    }
36}
37
38impl PartialEq<IntegerPolynomial> for Integer {
39    /// Determines whether an [`Integer`] is equal to an [`IntegerPolynomial`].
40    ///
41    /// The [`Integer`] is equal to the polynomial when the polynomial is the constant polynomial
42    /// with that value, so 0 is equal to the zero polynomial.
43    ///
44    /// # Worst-case complexity
45    /// $T(n) = O(n)$
46    ///
47    /// $M(n) = O(1)$
48    ///
49    /// where $T$ is time, $M$ is additional memory, and $n$ is `min(self.significant_bits(),
50    /// other.coefficient(0).significant_bits())`.
51    ///
52    /// # Examples
53    /// See [here](super::partial_eq_integer#partial_eq).
54    #[inline]
55    fn eq(&self, other: &IntegerPolynomial) -> bool {
56        other == self
57    }
58}