finetime 0.8.1

High-fidelity time library for applications where sub-nanosecond accuracy and exact arithmetic are needed
Documentation 
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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276

//! Definitions of the different units that may be used to express `Duration`s. In essence, these
//! types are little more than labels that are associated with a given ratio to SI seconds, as may
//! be used to convert between arbitrary time periods.

#[cfg(feature = "i256")]
use i256::{I256, U256};

use crate::{Fraction, TryMul};

/// Trait representing a lossless conversion from one unit to another. Note that the underlying
/// value representation stays the same. For floating point representations, floating point
/// rounding is permitted.
pub trait ConvertUnit<From, Into>
where
    From: ?Sized,
    Into: ?Sized,
{
    /// Converts from one unit into another. Shall only be used for exact conversions, without
    /// rounding error. Floating point errors are permitted.
    fn convert(self) -> Self;
}

macro_rules! impl_identity_conversion {
    ($repr:ty) => {
        impl<T> ConvertUnit<T, T> for $repr
        where
            T: UnitRatio,
        {
            fn convert(self) -> Self {
                self
            }
        }
    };
}

impl_identity_conversion!(u8);
impl_identity_conversion!(u16);
impl_identity_conversion!(u32);
impl_identity_conversion!(u64);
impl_identity_conversion!(u128);
#[cfg(feature = "i256")]
impl_identity_conversion!(U256);
impl_identity_conversion!(i8);
impl_identity_conversion!(i16);
impl_identity_conversion!(i32);
impl_identity_conversion!(i64);
impl_identity_conversion!(i128);
#[cfg(feature = "i256")]
impl_identity_conversion!(I256);

impl<From, Into> ConvertUnit<From, Into> for f64
where
    From: UnitRatio + ?Sized,
    Into: UnitRatio + ?Sized,
{
    fn convert(self) -> Self {
        let combined_ratio = From::FRACTION.divide_by(&Into::FRACTION);
        combined_ratio * self
    }
}

impl<From, Into> ConvertUnit<From, Into> for f32
where
    From: UnitRatio + ?Sized,
    Into: UnitRatio + ?Sized,
{
    fn convert(self) -> Self {
        let combined_ratio = From::FRACTION.divide_by(&Into::FRACTION);
        combined_ratio * self
    }
}

/// Trait representing a fallible conversion from one unit to another, failing if the requested
/// conversion cannot be computed losslessly. For floating point representations, this conversion
/// shall always succeed.
pub trait TryConvertUnit<From, Into>: Sized
where
    From: ?Sized,
    Into: ?Sized,
{
    /// Tries to convert from one unit into another. If the conversion would result in significant
    /// (non floating point) rounding error, returns `None`.
    fn try_convert(self) -> Option<Self>;
}

impl<T, From, Into> TryConvertUnit<From, Into> for T
where
    T: TryMul<Fraction, Output = T>,
    From: UnitRatio + ?Sized,
    Into: UnitRatio + ?Sized,
{
    fn try_convert(self) -> Option<Self> {
        let combined_ratio = From::FRACTION.divide_by(&Into::FRACTION);
        self.try_mul(combined_ratio)
    }
}

/// Trait representing the fact that something is a unit ratio.
pub trait UnitRatio {
    const FRACTION: Fraction;
}

/// Unit that is described as an exact ratio with respect to unity.
#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum LiteralRatio<const NUMERATOR: u128, const DENOMINATOR: u128 = 1> {}

impl<const NUMERATOR: u128, const DENOMINATOR: u128> UnitRatio
    for LiteralRatio<NUMERATOR, DENOMINATOR>
{
    const FRACTION: Fraction = Fraction::new(NUMERATOR, DENOMINATOR);
}

macro_rules! valid_integer_conversions {
    (
        $from:ty => $( $to:ty ),+ $(,)?
    ) => {
        $(
            valid_integer_conversion!(u8, $from, $to);
            valid_integer_conversion!(u16, $from, $to);
            valid_integer_conversion!(u32, $from, $to);
            valid_integer_conversion!(u64, $from, $to);
            valid_integer_conversion!(u128, $from, $to);
            valid_integer_conversion!(i8, $from, $to);
            valid_integer_conversion!(i16, $from, $to);
            valid_integer_conversion!(i32, $from, $to);
            valid_integer_conversion!(i64, $from, $to);
            valid_integer_conversion!(i128, $from, $to);

            #[cfg(feature = "i256")]
            impl ConvertUnit<$from, $to> for U256 {
                fn convert(self) -> Self {
                    let combined_ratio = <$from>::FRACTION.divide_by(&<$to>::FRACTION);
                    // For any conversion ratio that is lossless, this division will not truncate.
                    let factor = combined_ratio.numerator() / combined_ratio.denominator();
                    self * Self::from(factor)
                }
            }

            #[cfg(feature = "i256")]
            impl ConvertUnit<$from, $to> for I256 {
                fn convert(self) -> Self {
                    let combined_ratio = <$from>::FRACTION.divide_by(&<$to>::FRACTION);
                    // For any conversion ratio that is lossless, this division will not truncate.
                    let factor = combined_ratio.numerator() / combined_ratio.denominator();
                    self * Self::from(factor)
                }
            }
        )+
    };
}

macro_rules! valid_integer_conversion {
    ($repr:ty, $from:ty, $into:ty) => {
        impl ConvertUnit<$from, $into> for $repr {
            fn convert(self) -> Self {
                let combined_ratio = <$from>::FRACTION.divide_by(&<$into>::FRACTION);
                // For any conversion ratio that is lossless, this division will not truncate.
                let factor = combined_ratio.numerator() / combined_ratio.denominator();
                self * (factor as Self)
            }
        }
    };
}

// SI unit qualifiers
pub type Quecto = LiteralRatio<1, 1_000_000_000_000_000_000_000_000_000_000>;
pub type Ronto = LiteralRatio<1, 1_000_000_000_000_000_000_000_000_000>;
pub type Yocto = LiteralRatio<1, 1_000_000_000_000_000_000_000_000>;
pub type Zepto = LiteralRatio<1, 1_000_000_000_000_000_000_000>;
pub type Atto = LiteralRatio<1, 1_000_000_000_000_000_000>;
pub type Femto = LiteralRatio<1, 1_000_000_000_000_000>;
pub type Pico = LiteralRatio<1, 1_000_000_000_000>;
pub type Nano = LiteralRatio<1, 1_000_000_000>;
pub type Micro = LiteralRatio<1, 1_000_000>;
pub type Milli = LiteralRatio<1, 1_000>;
pub type Centi = LiteralRatio<1, 100>;
pub type Deci = LiteralRatio<1, 10>;
pub type Deca = LiteralRatio<10>;
pub type Hecto = LiteralRatio<100>;
pub type Kilo = LiteralRatio<1_000>;
pub type Mega = LiteralRatio<1_000_000>;
pub type Giga = LiteralRatio<1_000_000_000>;
pub type Tera = LiteralRatio<1_000_000_000_000>;
pub type Peta = LiteralRatio<1_000_000_000_000_000>;
pub type Exa = LiteralRatio<1_000_000_000_000_000_000>;
pub type Zetta = LiteralRatio<1_000_000_000_000_000_000_000>;
pub type Yotta = LiteralRatio<1_000_000_000_000_000_000_000_000>;
pub type Ronna = LiteralRatio<1_000_000_000_000_000_000_000_000_000>;
pub type Quetta = LiteralRatio<1_000_000_000_000_000_000_000_000_000_000>;

// Conversions between regular SI units
valid_integer_conversions!(Ronto => Quecto);
valid_integer_conversions!(Yocto => Ronto, Quecto);
valid_integer_conversions!(Zepto => Yocto, Ronto, Quecto);
valid_integer_conversions!(Atto => Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Femto => Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Pico => Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Nano => Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Micro => Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Milli => Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Centi => Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Deci => Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Second => Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Deca => Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Hecto => Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Kilo => Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Mega => Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Giga => Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Tera => Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Peta => Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Exa => Peta, Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Zetta => Exa, Peta, Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Yotta => Zetta, Exa, Peta, Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Ronna => Yotta, Zetta, Exa, Peta, Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);
valid_integer_conversions!(Quetta => Ronna, Yotta, Zetta, Exa, Peta, Tera, Giga, Mega, Kilo, Hecto, Deca, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto, Zepto, Yocto, Ronto, Quecto);

// Time unit qualifiers
pub type Second = LiteralRatio<1>;
pub type SecondsPerMinute = LiteralRatio<60>;
pub type SecondsPerHour = LiteralRatio<3600>;
/// Represents the number of seconds in half a day. Rather arbitrary "unit ratio", but turns out to
/// be useful in representing Julian days and modified Julian days.
pub type SecondsPerHalfDay = LiteralRatio<43200>;
pub type SecondsPerDay = LiteralRatio<86400>;
pub type SecondsPerWeek = LiteralRatio<604800>;
/// The number of seconds in 1/12 the average Gregorian year.
pub type SecondsPerMonth = LiteralRatio<2629746>;
/// The number of seconds in an average Gregorian year.
pub type SecondsPerYear = LiteralRatio<31556952>;

// Conversions specific to time units
valid_integer_conversions!(SecondsPerMinute => Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerHour => SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerHalfDay => SecondsPerHour, SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerDay => SecondsPerHalfDay, SecondsPerHour, SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerWeek => SecondsPerDay, SecondsPerHalfDay, SecondsPerHour, SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerMonth => SecondsPerWeek, SecondsPerDay, SecondsPerHalfDay, SecondsPerHour, SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);
valid_integer_conversions!(SecondsPerYear => SecondsPerMonth, SecondsPerWeek, SecondsPerDay, SecondsPerHalfDay, SecondsPerHour, SecondsPerMinute, Second, Deci, Centi, Milli, Micro, Nano, Pico, Femto, Atto);

// Binary fractions of X bytes
pub type BinaryFraction1 = LiteralRatio<1, 0x100>;
pub type BinaryFraction2 = LiteralRatio<1, 0x10000>;
pub type BinaryFraction3 = LiteralRatio<1, 0x1000000>;
pub type BinaryFraction4 = LiteralRatio<1, 0x100000000>;
pub type BinaryFraction5 = LiteralRatio<1, 0x10000000000>;
pub type BinaryFraction6 = LiteralRatio<1, 0x1000000000000>;
pub type BinaryFraction7 = LiteralRatio<1, 0x100000000000000>;
pub type BinaryFraction8 = LiteralRatio<1, 0x10000000000000000>;
pub type BinaryFraction9 = LiteralRatio<1, 0x1000000000000000000>;
pub type BinaryFraction10 = LiteralRatio<1, 0x100000000000000000000>;

// Conversions for binary fractions
valid_integer_conversions!(BinaryFraction9 => BinaryFraction10);
valid_integer_conversions!(BinaryFraction8 => BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction7 => BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction6 => BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction5 => BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction4 => BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction3 => BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction2 => BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(BinaryFraction1 => BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Second => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Deca => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Hecto => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Kilo => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Mega => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Giga => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Tera => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Peta => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(Exa => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerMinute => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerHour => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerDay => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerWeek => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerMonth => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);
valid_integer_conversions!(SecondsPerYear => BinaryFraction1, BinaryFraction2, BinaryFraction3, BinaryFraction4, BinaryFraction5, BinaryFraction6, BinaryFraction7, BinaryFraction8, BinaryFraction9, BinaryFraction10);