1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205
// Copyright © 2024 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use crate::integer::Integer;
use crate::natural::Natural;
use malachite_base::num::basic::traits::Zero;
use malachite_base::num::conversion::traits::{ConvertibleFrom, SaturatingFrom};
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct NaturalFromIntegerError;
impl TryFrom<Integer> for Natural {
type Error = NaturalFromIntegerError;
/// Converts an [`Integer`] to a [`Natural`], taking the [`Natural`] by value. If the
/// [`Integer`] is negative, an error is returned.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::strings::ToDebugString;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::try_from(Integer::from(123)).to_debug_string(), "Ok(123)");
/// assert_eq!(
/// Natural::try_from(Integer::from(-123)).to_debug_string(),
/// "Err(NaturalFromIntegerError)"
/// );
/// assert_eq!(
/// Natural::try_from(Integer::from(10u32).pow(12)).to_debug_string(),
/// "Ok(1000000000000)"
/// );
/// assert_eq!(
/// Natural::try_from(-Integer::from(10u32).pow(12)).to_debug_string(),
/// "Err(NaturalFromIntegerError)"
/// );
/// ```
fn try_from(value: Integer) -> Result<Natural, Self::Error> {
match value {
Integer { sign: false, .. } => Err(NaturalFromIntegerError),
Integer { sign: true, abs } => Ok(abs),
}
}
}
impl<'a> TryFrom<&'a Integer> for Natural {
type Error = NaturalFromIntegerError;
/// Converts an [`Integer`] to a [`Natural`], taking the [`Natural`] by reference. If the
/// [`Integer`] is negative, an error is returned.
///
/// # Worst-case complexity
/// $T(n) = O(n)$
///
/// $M(n) = O(n)$
///
/// where $T$ is time, $M$ is additional memory, and $n$ is `value.significant_bits()`.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::strings::ToDebugString;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::try_from(&Integer::from(123)).to_debug_string(), "Ok(123)");
/// assert_eq!(
/// Natural::try_from(&Integer::from(-123)).to_debug_string(),
/// "Err(NaturalFromIntegerError)"
/// );
/// assert_eq!(
/// Natural::try_from(&Integer::from(10u32).pow(12)).to_debug_string(),
/// "Ok(1000000000000)"
/// );
/// assert_eq!(
/// Natural::try_from(&(-Integer::from(10u32).pow(12))).to_debug_string(),
/// "Err(NaturalFromIntegerError)"
/// );
/// ```
fn try_from(value: &'a Integer) -> Result<Natural, Self::Error> {
match *value {
Integer { sign: false, .. } => Err(NaturalFromIntegerError),
Integer {
sign: true,
ref abs,
} => Ok(abs.clone()),
}
}
}
impl SaturatingFrom<Integer> for Natural {
/// Converts an [`Integer`] to a [`Natural`], taking the [`Natural`] by value. If the
/// [`Integer`] is negative, 0 is returned.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::num::conversion::traits::SaturatingFrom;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::saturating_from(Integer::from(123)), 123);
/// assert_eq!(Natural::saturating_from(Integer::from(-123)), 0);
/// assert_eq!(Natural::saturating_from(Integer::from(10u32).pow(12)), 1000000000000u64);
/// assert_eq!(Natural::saturating_from(-Integer::from(10u32).pow(12)), 0);
/// ```
fn saturating_from(value: Integer) -> Natural {
match value {
Integer { sign: false, .. } => Natural::ZERO,
Integer { sign: true, abs } => abs,
}
}
}
impl<'a> SaturatingFrom<&'a Integer> for Natural {
/// Converts an [`Integer`] to a [`Natural`], taking the [`Natural`] by reference. If the
/// [`Integer`] is negative, 0 is returned.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::num::conversion::traits::SaturatingFrom;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::saturating_from(&Integer::from(123)), 123);
/// assert_eq!(Natural::saturating_from(&Integer::from(-123)), 0);
/// assert_eq!(Natural::saturating_from(&Integer::from(10u32).pow(12)), 1000000000000u64);
/// assert_eq!(Natural::saturating_from(&-Integer::from(10u32).pow(12)), 0);
/// ```
fn saturating_from(value: &'a Integer) -> Natural {
match *value {
Integer { sign: false, .. } => Natural::ZERO,
Integer {
sign: true,
ref abs,
} => abs.clone(),
}
}
}
impl ConvertibleFrom<Integer> for Natural {
/// Determines whether an [`Integer`] can be converted to a [`Natural`] (when the [`Integer`] is
/// non-negative). Takes the [`Integer`] by value.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::num::conversion::traits::ConvertibleFrom;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::convertible_from(Integer::from(123)), true);
/// assert_eq!(Natural::convertible_from(Integer::from(-123)), false);
/// assert_eq!(Natural::convertible_from(Integer::from(10u32).pow(12)), true);
/// assert_eq!(Natural::convertible_from(-Integer::from(10u32).pow(12)), false);
/// ```
#[inline]
fn convertible_from(value: Integer) -> bool {
value.sign
}
}
impl<'a> ConvertibleFrom<&'a Integer> for Natural {
/// Determines whether an [`Integer`] can be converted to a [`Natural`] (when the [`Integer`] is
/// non-negative). Takes the [`Integer`] by reference.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Pow;
/// use malachite_base::num::conversion::traits::ConvertibleFrom;
/// use malachite_nz::integer::Integer;
/// use malachite_nz::natural::Natural;
///
/// assert_eq!(Natural::convertible_from(&Integer::from(123)), true);
/// assert_eq!(Natural::convertible_from(&Integer::from(-123)), false);
/// assert_eq!(Natural::convertible_from(&Integer::from(10u32).pow(12)), true);
/// assert_eq!(Natural::convertible_from(&-Integer::from(10u32).pow(12)), false);
/// ```
#[inline]
fn convertible_from(value: &'a Integer) -> bool {
value.sign
}
}