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
|
use std::{
fmt,
ops::{Add, Div, Mul, Sub},
};
use crate::lisp::error::LispError;
#[derive(Debug, Copy, Clone)]
pub enum LispNumber {
Integer(i64),
Float(f64),
}
impl LispNumber {
pub fn div(self, rhs: Self) -> Result<LispNumber, LispError> {
use LispNumber::*;
if rhs == Integer(0) || rhs == Float(0.) {
return Err(LispError::EvalError);
} else {
return Ok(match (self, rhs) {
(Integer(a), Integer(b)) => Float(a as f64 / b as f64),
(Float(a), Integer(b)) => Float(a / b as f64),
(Integer(a), Float(b)) => Float(a as f64 / b),
(Float(a), Float(b)) => Float(a / b),
});
}
}
}
impl Add for LispNumber {
type Output = Self;
fn add(self, rhs: Self) -> Self::Output {
use LispNumber::*;
match (self, rhs) {
(Integer(a), Integer(b)) => Integer(a + b),
(Float(a), Integer(b)) => Float(a + b as f64),
(Integer(a), Float(b)) => Float(a as f64 + b),
(Float(a), Float(b)) => Float(a + b),
}
}
}
impl Sub for LispNumber {
type Output = Self;
fn sub(self, rhs: Self) -> Self::Output {
use LispNumber::*;
match (self, rhs) {
(Integer(a), Integer(b)) => Integer(a - b),
(Float(a), Integer(b)) => Float(a - b as f64),
(Integer(a), Float(b)) => Float(a as f64 - b),
(Float(a), Float(b)) => Float(a - b),
}
}
}
impl Mul for LispNumber {
type Output = Self;
fn mul(self, rhs: Self) -> Self::Output {
use LispNumber::*;
match (self, rhs) {
(Integer(a), Integer(b)) => Integer(a * b),
(Float(a), Integer(b)) => Float(a * b as f64),
(Integer(a), Float(b)) => Float(a as f64 * b),
(Float(a), Float(b)) => Float(a * b),
}
}
}
impl PartialEq for LispNumber {
fn eq(&self, other: &Self) -> bool {
use LispNumber::*;
match (self, other) {
(Integer(a), Integer(b)) => *a == *b,
(Float(a), Integer(b)) => *a == *b as f64,
(Integer(a), Float(b)) => *a as f64 == *b,
(Float(a), Float(b)) => *a == *b,
}
}
}
impl fmt::Display for LispNumber {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
LispNumber::Integer(v) => write!(f, "{}", v),
LispNumber::Float(v) => write!(f, "{}", v),
}
}
}
|
