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
use core::fmt;
use num_traits::{CheckedAdd, CheckedSub, Num};
use super::{Btrit, ShiftTernary, Trit};
use crate::convert;
#[derive(Copy, Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
#[repr(i8)]
#[allow(missing_docs)]
pub enum Utrit {
Zero = 0,
One = 1,
Two = 2,
}
use Utrit::*;
impl fmt::Display for Utrit {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", *self as i8)
}
}
impl From<Utrit> for i8 {
fn from(value: Utrit) -> Self {
value as i8
}
}
impl ShiftTernary for Utrit {
type Target = Btrit;
fn shift(self) -> Self::Target {
match self {
Zero => Self::Target::NegOne,
One => Self::Target::Zero,
Two => Self::Target::PlusOne,
}
}
}
impl Trit for Utrit {
fn checked_increment(self) -> Option<Self> {
match self {
Zero => Some(One),
One => Some(Two),
Two => None,
}
}
fn zero() -> Self {
Self::Zero
}
fn as_arbitrary_ref<'a>(&self) -> &'a Self {
static ZERO: Utrit = Utrit::Zero;
static ONE: Utrit = Utrit::One;
static TWO: Utrit = Utrit::Two;
match self {
Utrit::Zero => &ZERO,
Utrit::One => &ONE,
Utrit::Two => &TWO,
}
}
fn add_to_num<I: Num + CheckedAdd + CheckedSub>(&self, n: I) -> Result<I, convert::Error> {
match self {
Utrit::Zero => Ok(n),
Utrit::One => n.checked_add(&I::one()).ok_or(convert::Error::Overflow),
Utrit::Two => n.checked_add(&(I::one() + I::one())).ok_or(convert::Error::Overflow),
}
}
}
impl Utrit {
pub(crate) fn from_u8(x: u8) -> Self {
match x {
0 => Zero,
1 => One,
2 => Two,
x => panic!("Invalid trit representation '{}'", x),
}
}
pub(crate) fn into_u8(self) -> u8 {
match self {
Zero => 0,
One => 1,
Two => 2,
}
}
}
impl TryFrom<i8> for Utrit {
type Error = ();
fn try_from(x: i8) -> Result<Self, Self::Error> {
let converted = match x {
0 => Zero,
1 => One,
2 => Two,
_ => return Err(()),
};
Ok(converted)
}
}
impl TryFrom<u8> for Utrit {
type Error = ();
fn try_from(x: u8) -> Result<Self, Self::Error> {
let converted = match x {
0 => Zero,
1 => One,
2 => Two,
_ => return Err(()),
};
Ok(converted)
}
}
