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
|
use core::num::Wrapping;
use core::{f32, f64};
#[cfg(has_i128)]
use core::{i128, u128};
use core::{i16, i32, i64, i8, isize};
use core::{u16, u32, u64, u8, usize};
/// Numbers which have upper and lower bounds
pub trait Bounded {
// FIXME (#5527): These should be associated constants
/// Returns the smallest finite number this type can represent
fn min_value() -> Self;
/// Returns the largest finite number this type can represent
fn max_value() -> Self;
}
/// Numbers which have lower bounds
pub trait LowerBounded {
/// Returns the smallest finite number this type can represent
fn min_value() -> Self;
}
// FIXME: With a major version bump, this should be a supertrait instead
impl<T: Bounded> LowerBounded for T {
fn min_value() -> T {
Bounded::min_value()
}
}
/// Numbers which have upper bounds
pub trait UpperBounded {
/// Returns the largest finite number this type can represent
fn max_value() -> Self;
}
// FIXME: With a major version bump, this should be a supertrait instead
impl<T: Bounded> UpperBounded for T {
fn max_value() -> T {
Bounded::max_value()
}
}
macro_rules! bounded_impl {
($t:ty, $min:expr, $max:expr) => {
impl Bounded for $t {
#[inline]
fn min_value() -> $t {
$min
}
#[inline]
fn max_value() -> $t {
$max
}
}
};
}
bounded_impl!(usize, usize::MIN, usize::MAX);
bounded_impl!(u8, u8::MIN, u8::MAX);
bounded_impl!(u16, u16::MIN, u16::MAX);
bounded_impl!(u32, u32::MIN, u32::MAX);
bounded_impl!(u64, u64::MIN, u64::MAX);
#[cfg(has_i128)]
bounded_impl!(u128, u128::MIN, u128::MAX);
bounded_impl!(isize, isize::MIN, isize::MAX);
bounded_impl!(i8, i8::MIN, i8::MAX);
bounded_impl!(i16, i16::MIN, i16::MAX);
bounded_impl!(i32, i32::MIN, i32::MAX);
bounded_impl!(i64, i64::MIN, i64::MAX);
#[cfg(has_i128)]
bounded_impl!(i128, i128::MIN, i128::MAX);
impl<T: Bounded> Bounded for Wrapping<T> {
fn min_value() -> Self {
Wrapping(T::min_value())
}
fn max_value() -> Self {
Wrapping(T::max_value())
}
}
bounded_impl!(f32, f32::MIN, f32::MAX);
macro_rules! for_each_tuple_ {
( $m:ident !! ) => (
$m! { }
);
( $m:ident !! $h:ident, $($t:ident,)* ) => (
$m! { $h $($t)* }
for_each_tuple_! { $m !! $($t,)* }
);
}
macro_rules! for_each_tuple {
($m:ident) => {
for_each_tuple_! { $m !! A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, }
};
}
macro_rules! bounded_tuple {
( $($name:ident)* ) => (
impl<$($name: Bounded,)*> Bounded for ($($name,)*) {
#[inline]
fn min_value() -> Self {
($($name::min_value(),)*)
}
#[inline]
fn max_value() -> Self {
($($name::max_value(),)*)
}
}
);
}
for_each_tuple!(bounded_tuple);
bounded_impl!(f64, f64::MIN, f64::MAX);
#[test]
fn wrapping_bounded() {
macro_rules! test_wrapping_bounded {
($($t:ty)+) => {
$(
assert_eq!(<Wrapping<$t> as Bounded>::min_value().0, <$t>::min_value());
assert_eq!(<Wrapping<$t> as Bounded>::max_value().0, <$t>::max_value());
)+
};
}
test_wrapping_bounded!(usize u8 u16 u32 u64 isize i8 i16 i32 i64);
}
#[cfg(has_i128)]
#[test]
fn wrapping_bounded_i128() {
macro_rules! test_wrapping_bounded {
($($t:ty)+) => {
$(
assert_eq!(<Wrapping<$t> as Bounded>::min_value().0, <$t>::min_value());
assert_eq!(<Wrapping<$t> as Bounded>::max_value().0, <$t>::max_value());
)+
};
}
test_wrapping_bounded!(u128 i128);
}
#[test]
fn wrapping_is_bounded() {
fn require_bounded<T: Bounded>(_: &T) {}
require_bounded(&Wrapping(42_u32));
require_bounded(&Wrapping(-42));
}
|
