diff options
Diffstat (limited to 'src/lib.rs')
| -rw-r--r-- | src/lib.rs | 219 |
1 files changed, 218 insertions, 1 deletions
@@ -344,7 +344,7 @@ macro_rules! free { #[cfg(test)] mod free_monad_tests{ - use higher::{Pure, Functor, Bind, Apply}; + use higher::{Pure, Functor, Bind, Apply, apply::ApplyFn}; use super::free; @@ -487,7 +487,224 @@ mod free_monad_tests{ } } + //need Bind and Pure to test retract. This is dumb, but it should fulfill the monad laws: + impl<'a, A : 'a, B : 'a> Bind<'a, A> for Conti<'a,A,B> where B : Clone{ + type Target<T> = Conti<'a,T,B>; + + fn bind<C, F>(self, f: F) -> Self::Target<C> where F: Fn(A) -> Self::Target<C> + 'a { + let f = Rc::new(f); + let g = f.clone(); + let l = move |x| f((self.0)(x)); + let r = move |x| g((self.1)(x)); + Conti(Rc::new(move |x| (l(x.clone())).0(x)), Rc::new(move |x| (r(x.clone())).1(x))) + } + } + impl<'a, A : 'a, B : 'a> Pure<A> for Conti<'a,A,B> where A : Clone{ + fn pure(value: A) -> Self { + let v2 = value.clone(); + Conti(Rc::new(move |_| value.clone()), Rc::new(move |_| v2.clone())) + } + } + + //I really am not certain if the Pure and Bind above are correct. Sooo, why not test those too, while we are at it? + #[test] + fn test_conti_monad_laws(){ + let b = |x : u32| { + let y = x.clone(); + Conti::<u32,u32>(Rc::new(move |a| x.clone() + a*2), Rc::new(move |a| y.clone() * a+3)) + }; + let t1 = Conti::pure(7u32); + let v1 = t1.bind(b); + let v2 = b(7u32); + assert_eq!((v1.0)(13), (v2.0)(13)); + assert_eq!((v1.1)(17), (v2.1)(17)); + + let c = Conti(Rc::new(|a| 31 + a*5), Rc::new(|b| 32*b+3)); + let d =c.clone().bind(Conti::pure); + assert_eq!((c.0)(3), (d.0)(3)); + assert_eq!((c.1)(5), (d.1)(5)); + + let m = Conti(Rc::new(|a| 32 + (a*2)), Rc::new(|b| 32*b+7)); + let g = |x : u32| { + let y = x.clone(); + Conti::<u32,u32>(Rc::new(move |a| x.clone()*2 + a), Rc::new(move |a| y.clone() * a+7)) + }; + let h = |x : u32| { + let y = x.clone(); + Conti::<u32,u32>(Rc::new(move |a| x.clone() + a), Rc::new(move |a| y.clone() * a+12)) + }; + + let v1 = (m.clone().bind(g.clone())).bind(h.clone()); + let v2 = m.bind(|a| (g(a).bind(h))); + assert_eq!((v1.0)(37), (v2.0)(37)); + assert_eq!((v1.1)(41), (v2.1)(41)); + + //well, looks monadic enough to me. Let's use it for the unit test of retract below. + } + + free!(<'a>, FreeConti<'a,A,B>, Conti<'a,FreeConti<'a,A,B>,B>); + #[test] + fn test_lift_f_lifetime(){ + let f = FreeConti::lift_f(Conti(Rc::new((|x| x*2) as fn(u32) -> u32), Rc::new((|x| x+5) as fn(u32) -> u32))); + match f { + FreeConti::Free(m) => { + match (m.0)(4){ + FreeConti::Pure(v) => assert_eq!(v, 8), + _ => unreachable!() + } + match (m.1)(4){ + FreeConti::Pure(v) => assert_eq!(v, 9), + _ => unreachable!() + } + }, + _ => unreachable!() + } + } + + #[test] + fn test_retract_lifetime(){ + let f = FreeConti::lift_f(Conti(Rc::new((|x| x*2) as fn(u32) -> u32), Rc::new((|x| x+5) as fn(u32) -> u32))); + let r = f.retract(); + assert_eq!((r.0)(4), 8); + assert_eq!((r.1)(4), 9); + } + + #[test] + fn test_fmap_lifetime(){ + let c = Conti(Rc::new(|x : u32| (x as i32)*3+2), Rc::new(|x| ((x as i32)+2)*5)); + let f = FreeConti::lift_f(c); + let f = f.fmap(|x : i32| (x as f32)*0.25f32); + match f { + FreeConti::Free(f) => { + let l = (f.0)(7); + match l { + FreeConti::Pure(v) => { + assert_eq!(v, 5.75f32); + }, + _ => unreachable!() + } + let r = (f.1)(7); + match r { + FreeConti::Pure(v) => { + assert_eq!(v, 11.25f32); + }, + _ => unreachable!() + } + }, + _ => unreachable!() + } + } + + #[test] + fn test_pure_lifetime(){ + let f : FreeConti<_,()> = FreeConti::pure(27); + match f { + FreeConti::Pure(v) => assert_eq!(v, 27), + FreeConti::Free(_) => unreachable!(), + } + } + + #[test] + fn test_bind_lifetime(){ + let c = Conti(Rc::new(|x : u32| (x as i32)*3+2), Rc::new(|x| ((x as i32)+2)*5)); + let f = FreeConti::lift_f(c); + let f = f.bind(|y| { + let z = y.clone(); + FreeConti::lift_f(Conti(Rc::new(move |x| (x as f32)*0.25f32 + (y as f32)), Rc::new(move |x| (x as f32) * 0.5f32 - (z as f32)))) + }); + match f { + FreeConti::Free(f) => { + let l = (f.0)(4); + match l { + FreeConti::Free(f) => { + //14i32 + let l = (f.0)(5); + match l { + FreeConti::Pure(v) => assert_eq!(v, 15.25f32), + FreeConti::Free(_) => unreachable!(), + } + let r = (f.1)(5); + match r{ + FreeConti::Pure(v) => assert_eq!(v, -11.5f32), + FreeConti::Free(_) => unreachable!(), + } + }, + FreeConti::Pure(_) => unreachable!(), + } + let r = (f.1)(4); + match r { + FreeConti::Free(f) => { + //30i32 + let l = (f.0)(5); + match l { + FreeConti::Pure(v) => assert_eq!(v, 31.25f32), + FreeConti::Free(_) => unreachable!(), + } + let r = (f.1)(5); + match r { + FreeConti::Pure(v) => assert_eq!(v, -27.5f32), + FreeConti::Free(_) => unreachable!(), + } + }, + FreeConti::Pure(_) => unreachable!(), + } + }, + _ => unreachable!() + } + } + + #[test] + fn test_apply_lifetime(){ + //oh, god, please no. + let m = FreeConti::lift_f(Conti(Rc::new(|x : u32| (x as i32)*3+2), Rc::new(|x| ((x as i32)+2)*5))); + let f = FreeConti::lift_f(Conti(Rc::new(|x : u32| -> ApplyFn<i32,f32> { + (move |y : i32| (y + (x as i32)) as f32).into() + }), Rc::new(|x : u32| { + (move |y : i32| (y*(x as i32)) as f32).into() + }))); + //make it stop! + let m = m.apply(f); + + match m { + FreeConti::Free(m) => { + let l = (m.0)(5u32); + match l { + FreeConti::Free(m) => { + let l = (m.0)(7u32); + match l { + FreeConti::Pure(v) => assert_eq!(v,28f32), + FreeConti::Free(_) => unreachable!(), + } + let r = (m.1)(7u32); + match r { + FreeConti::Pure(v) => assert_eq!(v,50f32), + FreeConti::Free(_) => unreachable!(), + } + }, + FreeConti::Pure(_) => unreachable!(), + } + let r = (m.1)(5u32); + match r { + FreeConti::Free(m) => { + let l = (m.0)(7u32); + match l { + FreeConti::Pure(v) => assert_eq!(v,(5f32*23f32)), + FreeConti::Free(_) => unreachable!(), + } + let r = (m.1)(7u32); + match r { + FreeConti::Pure(v) => assert_eq!(v, 5f32*45f32), + FreeConti::Free(_) => unreachable!(), + } + }, + FreeConti::Pure(_) => unreachable!(), + } + }, + _ => unreachable!() + } + //let's never speak of this again. + } }
\ No newline at end of file |