xrunits/
length.rs

1use crate::{Unit, CastTo};
2use std::fmt::{Display, Formatter};
3
4pub trait Length : Unit + From<f64> {}
5
6macro_rules! build_type {
7    ($type_name : ident,
8     $trait_name : ident,
9     $short_name : ident,
10     $display_name : expr,
11     $num : expr,$den : expr) => {
12        #[derive(Debug,Copy,Clone,PartialEq,PartialOrd)]
13        pub struct $type_name(f64);
14        impl<T : Into<f64>> From<T> for $type_name {
15            fn from(other : T) -> Self {
16                $type_name(other.into())
17            }
18        }
19        pub trait $trait_name {
20            fn $short_name(self) -> $type_name;
21        }
22        impl<T : Into<f64>> $trait_name for T {
23            fn $short_name(self) -> $type_name {
24                $type_name(self.into())
25            }
26        }
27        impl Unit for $type_name {
28            const NUM: i32 = $num;
29            const DEN: i32 = $den;
30
31            fn value(&self) -> f64 {
32                self.0
33            }
34        }
35        impl Length for $type_name {}
36        impl Display for $type_name {
37            fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
38                write!(f,concat!("{}",$display_name),self.0)
39            }
40        }
41        impl<T : Length> CastTo<T> for $type_name {}
42    };
43}
44build_type!(Kilometer,BuildKilometer,km,"km",1000,1);
45build_type!(Meter,BuildMeter,m,"m",1,1);
46build_type!(Decimeter,BuildDecimeter,dm,"dm",1,10);
47build_type!(Centimeter,BuildCentimeter,cm,"cm",1,100);
48build_type!(Millimeter,BuildMillimeter,mm,"mm",1,1000);
49build_type!(Micrometer,BuildMicrometer,um,"um",1,1000_000);
50build_type!(Nanometer,BuildNanometer,nm,"nm",1,1000_000_000);
51
52#[cfg(test)]
53mod tests {
54    use crate::length::{BuildMeter, Centimeter, Millimeter};
55    use crate::CastTo;
56
57    #[test]
58    fn test() {
59        let m = 1.4444.m();
60        let cm : Centimeter = m.cast_to();
61        let mm : Millimeter = cm.cast_to();
62        println!("{}={}={}",m,cm,mm);
63    }
64}
xrunits/length.rs

xrunits/
length.rs
