12: Add solution to Rust track exercise "Space Age".

Dependencies

• [2] VXRUG632 11: Add Rust track exercise "Space Age".

Change contents

• replacement in rust/space-age/src/lib.rs at line 5
  [2.1780]→[2.1780:1801](∅→∅)
  − pub struct Duration;
  [2.1780]

  [2.1801]
  + pub struct Duration {

  + seconds: f64,

  + }
• replacement in rust/space-age/src/lib.rs at line 10
  [2.1832]→[2.1832:1924](∅→∅)
  − fn from(s: u64) -> Self {

  − unimplemented!("s, measured in seconds: {}", s)

  − }
  [2.1832]

  [2.1924]
  + fn from(s: u64) -> Self {

  + Duration { seconds: s as f64 }

  + }
• replacement in rust/space-age/src/lib.rs at line 16
  [2.1946]→[2.1946:2142](∅→∅)
  − fn years_during(d: &Duration) -> f64 {

  − unimplemented!(

  − "convert a duration ({:?}) to the number of years on this planet for that duration",

  − d,

  − );

  − }
  [2.1946]

  [2.2142]
  + fn years_during(d: &Duration) -> f64;
• replacement in rust/space-age/src/lib.rs at line 19
  [2.2145]→[2.2145:2296](∅→∅)
  − pub struct Mercury;

  − pub struct Venus;

  − pub struct Earth;

  − pub struct Mars;

  − pub struct Jupiter;

  − pub struct Saturn;

  − pub struct Uranus;

  − pub struct Neptune;
  [2.2145]

  [2.2296]
  + macro_rules! impl_planets {

  + ($($planet:ident : $period:literal),*) => {$(

  + pub struct $planet;

  + impl Planet for $planet {

  + fn years_during(d: &Duration) -> f64 {

  + d.seconds / 31557600.0 / $period

  + }

  + }

  + )*};

  + }
• replacement in rust/space-age/src/lib.rs at line 30
  [2.2297]→[2.2297:2504](∅→∅)
  − impl Planet for Mercury {}

  − impl Planet for Venus {}

  − impl Planet for Earth {}

  − impl Planet for Mars {}

  − impl Planet for Jupiter {}

  − impl Planet for Saturn {}

  − impl Planet for Uranus {}

  − impl Planet for Neptune {}
  [2.2297]
  + impl_planets! {

  + Mercury: 0.2408467,

  + Venus: 0.61519726,

  + Earth: 1.0,

  + Mars: 1.8808158,

  + Jupiter: 11.862615,

  + Saturn: 29.447498,

  + Uranus: 84.016846,

  + Neptune: 164.79132

  + }