.gitignore

@@ -1,3 +1,2 @@
 /target
 Cargo.lock
-.DS_Store

README.md

@@ -13,21 +13,14 @@ lenses::{_0, _1},
 fn main() {
     let a = ((1, 2), 3);
 
-    // use view to access inside the tuple
+    // combine lenses
-    let res = view(_0, a);
-    assert_eq!(res, (1, 2));
-
-    let res = view(_1, a);
-    assert_eq!(res, 3);
-
-    // you can combine lenses
     let lens = _0 + _1;
 
     // use the view function to access
     let res = view(lens, a);
     assert_eq!(res, 2);
 
-    // you can also call the lens as a function
+    // call the lens as a function
     let res = lens(a);
     assert_eq!(res, 2);
 
@@ -39,7 +32,7 @@ fn main() {
     let a = set(lens, a, 5);
     assert_eq!(a, ((1, 5), 3));
 
-    // you can also call the lens as a function to modify the value
+    // call the lens as a function to modify the value
     let res = lens(a, |v| v + 1);
     assert_eq!(res, ((1, 3), 3));
 }

examples/main.rs

@@ -1,23 +1,19 @@
-use bad_optics::lenses::*;
+use bad_optics::{
+    lenses::{_0, _1},
+    *,
+};
 
 fn main() {
     let a = ((1, 2), 3);
 
-    // use view to access inside the tuple
+    // combine lenses
-    let res = view(_0, a);
-    assert_eq!(res, (1, 2));
-
-    let res = view(_1, a);
-    assert_eq!(res, 3);
-
-    // you can combine lenses
     let lens = _0 + _1;
 
     // use the view function to access
     let res = view(lens, a);
     assert_eq!(res, 2);
 
-    // you can also call the lens as a function
+    // call the lens as a function
     let res = lens(a);
     assert_eq!(res, 2);
 
@@ -29,7 +25,7 @@ fn main() {
     let a = set(lens, a, 5);
     assert_eq!(a, ((1, 5), 3));
 
-    // you can also call the lens as a function to modify the value
+    // call the lens as a function to modify the value
     let res = lens(a, |v| v + 1);
-    assert_eq!(res, ((1, 6), 3));
+    assert_eq!(res, ((1, 3), 3));
 }

examples/struct_fields.rs

@@ -1,27 +0,0 @@
-use bad_optics::lenses::*;
-
-#[derive(Debug, PartialEq, Clone)]
-struct MyStruct {
-    hey: (u8, (u8, i32)),
-}
-
-fn main() {
-    // make a lens for Hello
-    let hey = lens(
-        |hello: MyStruct| hello.hey,
-        |mut hello: MyStruct, v| {
-            hello.hey = v;
-            hello
-        },
-    );
-
-    let my_struct = MyStruct { hey: (1, (2, -3)) };
-
-    // the thing we want to access
-    let thing = (my_struct, "hello");
-
-    // a lens that targets the -3 inside my_struct
-    let lens_that_targets_the_i32 = _0 + hey + _1 + _1;
-
-    assert_eq!(lens_that_targets_the_i32(thing), -3);
-}

src/combinations.rs

@@ -1,324 +1,42 @@
-use crate::{
+use crate::{Lens, LensOver, LensTrait, LensView};
-    lenses::{Lens, LensOver, LensView},
-    prisms::{Prism, PrismPreview},
-    traversals::{Traversal, TraversalOver, TraversalTraverse},
-};
 
 #[derive(Clone, Copy)]
 pub struct Combination<A, B>(A, B);
+impl<A, B> LensTrait for Combination<A, B> {}
 
-// additions
+impl<A, B> std::ops::Add<Lens<B>> for Lens<A>
-
+where
-// lens + lens
+    A: LensTrait,
-impl<A, B> std::ops::Add<Lens<B>> for Lens<A> {
+    B: LensTrait,
+{
     type Output = Lens<Combination<Lens<A>, Lens<B>>>;
 
     fn add(self, rhs: Lens<B>) -> Self::Output {
         Lens(Combination(self, rhs))
     }
 }
-// prism + prism
-impl<A, B> std::ops::Add<Prism<B>> for Prism<A> {
-    type Output = Prism<Combination<Prism<A>, Prism<B>>>;
 
-    fn add(self, rhs: Prism<B>) -> Self::Output {
+impl<A, B, T> LensView<T> for Combination<A, B>
-        Prism(Combination(self, rhs))
-    }
-}
-// traversal + traversal
-impl<A, B> std::ops::Add<Traversal<B>> for Traversal<A> {
-    type Output = Traversal<Combination<Traversal<A>, Traversal<B>>>;
-
-    fn add(self, rhs: Traversal<B>) -> Self::Output {
-        Traversal(Combination(self, rhs))
-    }
-}
-// traversal + lens
-impl<A, B> std::ops::Add<Lens<B>> for Traversal<A> {
-    type Output = Traversal<Combination<Traversal<A>, Traversal<Lens<B>>>>;
-
-    fn add(self, rhs: Lens<B>) -> Self::Output {
-        Traversal(Combination(self, rhs.to_traversal()))
-    }
-}
-// lens + traversal
-impl<A, B> std::ops::Add<Traversal<B>> for Lens<A> {
-    type Output = Traversal<Combination<Traversal<Lens<A>>, Traversal<B>>>;
-
-    fn add(self, rhs: Traversal<B>) -> Self::Output {
-        Traversal(Combination(self.to_traversal(), rhs))
-    }
-}
-// traversal + prism
-impl<A, B> std::ops::Add<Prism<B>> for Traversal<A> {
-    type Output = Traversal<Combination<Traversal<A>, Traversal<Prism<B>>>>;
-
-    fn add(self, rhs: Prism<B>) -> Self::Output {
-        Traversal(Combination(self, rhs.to_traversal()))
-    }
-}
-// prism + traversal
-impl<A, B> std::ops::Add<Traversal<B>> for Prism<A> {
-    type Output = Traversal<Combination<Traversal<Prism<A>>, Traversal<B>>>;
-
-    fn add(self, rhs: Traversal<B>) -> Self::Output {
-        Traversal(Combination(self.to_traversal(), rhs))
-    }
-}
-// lens + prism
-impl<A, B> std::ops::Add<Prism<B>> for Lens<A> {
-    type Output = Traversal<Combination<Traversal<Lens<A>>, Traversal<Prism<B>>>>;
-
-    fn add(self, rhs: Prism<B>) -> Self::Output {
-        Traversal(Combination(self.to_traversal(), rhs.to_traversal()))
-    }
-}
-// prism + traversal
-impl<A, B> std::ops::Add<Lens<B>> for Prism<A> {
-    type Output = Traversal<Combination<Traversal<Prism<A>>, Traversal<Lens<B>>>>;
-
-    fn add(self, rhs: Lens<B>) -> Self::Output {
-        Traversal(Combination(self.to_traversal(), rhs.to_traversal()))
-    }
-}
-
-// trait impls for Combination
-
-// lens + lens
-impl<A, B, T> LensView<T> for Combination<Lens<A>, Lens<B>>
 where
     A: LensView<T>,
     B: LensView<A::Field>,
 {
     type Field = B::Field;
 
-    fn view(&self, thing: T) -> Self::Field {
+    fn view(thing: T) -> Self::Field {
-        B::view(&self.1 .0, A::view(&self.0 .0, thing))
+        B::view(A::view(thing))
     }
 }
-impl<A, B, T> LensOver<T> for Combination<Lens<A>, Lens<B>>
+
+impl<A, B, T> LensOver<T> for Combination<A, B>
 where
     A: LensOver<T>,
     B: LensOver<A::Field>,
 {
-    fn over<F>(&self, thing: T, f: F) -> T
+    fn over<F>(thing: T, f: F) -> T
     where
         F: FnOnce(Self::Field) -> Self::Field,
     {
-        A::over(&self.0 .0, thing, |b| B::over(&self.1 .0, b, f))
+        A::over(thing, |b| B::over(b, f))
-    }
-}
-
-// prism + prism
-impl<A, B, T> PrismPreview<T> for Combination<Prism<A>, Prism<B>>
-where
-    A: PrismPreview<T>,
-    B: PrismPreview<A::Field>,
-{
-    type Field = B::Field;
-
-    fn preview(&self, thing: T) -> Option<Self::Field> {
-        A::preview(&self.0 .0, thing).and_then(|a| B::preview(&self.1 .0, a))
-    }
-
-    fn review(&self, thing: Self::Field) -> T {
-        A::review(&self.0 .0, B::review(&self.1 .0, thing))
-    }
-}
-
-// traversal + traversal
-// lens + traversal
-// traversal + lens
-// prism + traversal
-// traversal + prism
-// prism + lens
-// lens + prism
-impl<A, B, T> TraversalTraverse<T> for Combination<Traversal<A>, Traversal<B>>
-where
-    A: TraversalTraverse<T>,
-    B: TraversalTraverse<A::Field>,
-{
-    type Field = B::Field;
-
-    fn traverse(&self, thing: T) -> Vec<Self::Field> {
-        let a = A::traverse(&self.0 .0, thing);
-        a.into_iter()
-            .map(|v| B::traverse(&self.1 .0, v))
-            .flatten()
-            .collect()
-    }
-}
-impl<A, B, T> TraversalOver<T> for Combination<Traversal<A>, Traversal<B>>
-where
-    A: TraversalOver<T>,
-    B: TraversalOver<A::Field>,
-{
-    fn over<F>(&self, thing: T, mut f: F) -> T
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        A::over(&self.0 .0, thing, |b| B::over(&self.1 .0, b, &mut f))
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use crate::{
-        lenses::{_0, _1},
-        prisms::_Some,
-        traversals::each,
-    };
-
-    #[test]
-    fn can_view_lens_combination() {
-        let a = ((1, 2), 3);
-
-        let lens = _0 + _1;
-        let a = lens(a);
-        assert_eq!(a, 2);
-    }
-
-    #[test]
-    fn can_over_lens_combination() {
-        let a = ((1, 2), 3);
-
-        let lens = _0 + _1;
-        let a = lens(a, |v| v + 1);
-        assert_eq!(a, ((1, 3), 3));
-    }
-
-    #[test]
-    fn can_combine_prisms() {
-        let thing = Some(Some(3));
-
-        // combine two traversals
-        let res = (_Some + _Some)(thing, |v| v + 1);
-        assert_eq!(res, Some(Some(4)));
-    }
-
-    #[test]
-    fn can_combine_traversals() {
-        let array = [vec![1, 2], vec![3, 4]];
-
-        // combine two traversals
-        let res = (each + each)(array, |v| v + 1);
-        assert_eq!(res, [vec![2, 3], vec![4, 5]]);
-    }
-
-    #[test]
-    fn can_combine_traversal_with_lens() {
-        let array = [(1, 2), (3, 4), (5, 6)];
-
-        // combine a traversal with a lens
-        let t = each + _0;
-
-        // traverse
-        let res = t(array);
-        assert_eq!(res, vec![1, 3, 5]);
-
-        // over
-        let res = t(array, |v| v + 1);
-        assert_eq!(res, [(2, 2), (4, 4), (6, 6)]);
-    }
-
-    #[test]
-    fn can_combine_lens_with_traversal() {
-        let array = [(1, 2), (3, 4), (5, 6)];
-
-        // combine a traversal with a lens
-        let t = _0 + each;
-
-        // traverse
-        let res = t(array);
-        assert_eq!(res, vec![1, 2]);
-
-        // over
-        let res = t(array, |v| v + 1);
-        assert_eq!(res, [(2, 3), (3, 4), (5, 6)]);
-    }
-
-    #[test]
-    fn can_combine_prism_with_traversal() {
-        let array = [Some(1), None, Some(3), None, Some(5)];
-
-        // combine a traversal with a lens
-        let t = each + _Some;
-
-        // traverse
-        let res = t(array);
-        assert_eq!(res, vec![1, 3, 5]);
-
-        // over
-        let res = t(array, |v| v + 1);
-        assert_eq!(res, [Some(2), None, Some(4), None, Some(6)]);
-    }
-
-    #[test]
-    fn can_combine_traversal_with_prism() {
-        let array = Some([1, 2, 3]);
-
-        // combine a traversal with a lens
-        let t = _Some + each;
-
-        // traverse
-        let res = t(array);
-        assert_eq!(res, vec![1, 2, 3]);
-
-        // over
-        let res = t(array, |v| v + 1);
-        assert_eq!(res, Some([2, 3, 4]));
-
-        let array: Option<[i32; 3]> = None;
-        // traverse
-        let res = t(array);
-        assert_eq!(res, vec![]);
-
-        // over
-        let res = t(array, |v| v + 1);
-        assert_eq!(res, None);
-    }
-
-    #[test]
-    fn can_combine_prism_with_lens() {
-        let thing = Some((1, 2));
-
-        // combine a traversal with a lens
-        let t = _Some + _0;
-
-        // NOTE: combination of a prism and a lens is a traversal
-        //
-        // > The optic kind resulting from a composition is the least upper bound (join)
-        // > of the optic kinds being composed, if it exists.
-        // > The Join type family computes the least upper bound given two optic kind tags.
-        // > For example the Join of a Lens and a Prism is an AffineTraversal.
-        //
-        // from: https://hackage.haskell.org/package/optics-0.4/docs/Optics.html
-
-        // traversal
-        let res = t(thing);
-        assert_eq!(res, vec![1]);
-
-        // over
-        let res = t(thing, |v| v + 1);
-        assert_eq!(res, Some((2, 2)));
-    }
-
-    #[test]
-    fn can_combine_lens_with_prism() {
-        let thing = (Some(1), 2);
-
-        // combine a traversal with a lens
-        let t = _0 + _Some;
-
-        // NOTE: combination of a lens and a prism is a traversal
-        // see can_combine_prism_with_lens for more info
-
-        // traversal
-        let res = t(thing);
-        assert_eq!(res, vec![1]);
-
-        // over
-        let res = t(thing, |v| v + 1);
-        assert_eq!(res, (Some(2), 2));
     }
 }

src/fns.rs

@@ -1,10 +1,5 @@
-use crate::{
+use crate::{Lens, LensOver, LensView};
-    lenses::{Lens, LensOver, LensView},
-    prisms::{Prism, PrismPreview},
-    traversals::{Traversal, TraversalOver, TraversalTraverse},
-};
 
-// lens view
 impl<L, A> std::ops::FnOnce<(A,)> for Lens<L>
 where
     L: LensView<A>,
@@ -12,7 +7,7 @@ where
     type Output = L::Field;
 
     extern "rust-call" fn call_once(self, args: (A,)) -> Self::Output {
-        L::view(&self.0, args.0)
+        L::view(args.0)
     }
 }
 impl<L, A> std::ops::FnMut<(A,)> for Lens<L>
@@ -20,7 +15,7 @@ where
     L: LensView<A>,
 {
     extern "rust-call" fn call_mut(&mut self, args: (A,)) -> Self::Output {
-        L::view(&self.0, args.0)
+        L::view(args.0)
     }
 }
 impl<L, A> std::ops::Fn<(A,)> for Lens<L>
@@ -28,11 +23,10 @@ where
     L: LensView<A>,
 {
     extern "rust-call" fn call(&self, args: (A,)) -> Self::Output {
-        L::view(&self.0, args.0)
+        L::view(args.0)
     }
 }
 
-// lens over
 impl<L, A, F> std::ops::FnOnce<(A, F)> for Lens<L>
 where
     L: LensOver<A>,
@@ -41,7 +35,7 @@ where
     type Output = A;
 
     extern "rust-call" fn call_once(self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
+        L::over(args.0, args.1)
     }
 }
 impl<L, A, F> std::ops::FnMut<(A, F)> for Lens<L>
@@ -50,7 +44,7 @@ where
     F: FnOnce(L::Field) -> L::Field,
 {
     extern "rust-call" fn call_mut(&mut self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
+        L::over(args.0, args.1)
     }
 }
 impl<L, A, F> std::ops::Fn<(A, F)> for Lens<L>
@@ -59,127 +53,6 @@ where
     F: FnOnce(L::Field) -> L::Field,
 {
     extern "rust-call" fn call(&self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
+        L::over(args.0, args.1)
-    }
-}
-
-// traversal traverse
-impl<L, A> std::ops::FnOnce<(A,)> for Traversal<L>
-where
-    L: TraversalTraverse<A>,
-{
-    type Output = Vec<L::Field>;
-
-    extern "rust-call" fn call_once(self, args: (A,)) -> Self::Output {
-        L::traverse(&self.0, args.0)
-    }
-}
-impl<L, A> std::ops::FnMut<(A,)> for Traversal<L>
-where
-    L: TraversalTraverse<A>,
-{
-    extern "rust-call" fn call_mut(&mut self, args: (A,)) -> Self::Output {
-        L::traverse(&self.0, args.0)
-    }
-}
-impl<L, A> std::ops::Fn<(A,)> for Traversal<L>
-where
-    L: TraversalTraverse<A>,
-{
-    extern "rust-call" fn call(&self, args: (A,)) -> Self::Output {
-        L::traverse(&self.0, args.0)
-    }
-}
-
-// traversal over
-impl<L, A, F> std::ops::FnOnce<(A, F)> for Traversal<L>
-where
-    L: TraversalOver<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    type Output = A;
-
-    extern "rust-call" fn call_once(self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
-    }
-}
-impl<L, A, F> std::ops::FnMut<(A, F)> for Traversal<L>
-where
-    L: TraversalOver<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    extern "rust-call" fn call_mut(&mut self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
-    }
-}
-impl<L, A, F> std::ops::Fn<(A, F)> for Traversal<L>
-where
-    L: TraversalOver<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    extern "rust-call" fn call(&self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
-    }
-}
-
-// prism preview
-impl<L, A> std::ops::FnOnce<(A,)> for Prism<L>
-where
-    L: PrismPreview<A>,
-{
-    type Output = Option<L::Field>;
-
-    extern "rust-call" fn call_once(self, args: (A,)) -> Self::Output {
-        L::preview(&self.0, args.0)
-    }
-}
-impl<L, A> std::ops::FnMut<(A,)> for Prism<L>
-where
-    L: PrismPreview<A>,
-{
-    extern "rust-call" fn call_mut(&mut self, args: (A,)) -> Self::Output {
-        L::preview(&self.0, args.0)
-    }
-}
-impl<L, A> std::ops::Fn<(A,)> for Prism<L>
-where
-    L: PrismPreview<A>,
-{
-    extern "rust-call" fn call(&self, args: (A,)) -> Self::Output {
-        L::preview(&self.0, args.0)
-    }
-}
-
-// prism over
-impl<L, A, F> std::ops::FnOnce<(A, F)> for Prism<L>
-where
-    A: Clone,
-    L: PrismPreview<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    type Output = A;
-
-    extern "rust-call" fn call_once(self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
-    }
-}
-impl<L, A, F> std::ops::FnMut<(A, F)> for Prism<L>
-where
-    A: Clone,
-    L: PrismPreview<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    extern "rust-call" fn call_mut(&mut self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
-    }
-}
-impl<L, A, F> std::ops::Fn<(A, F)> for Prism<L>
-where
-    A: Clone,
-    L: PrismPreview<A>,
-    F: FnMut(L::Field) -> L::Field,
-{
-    extern "rust-call" fn call(&self, args: (A, F)) -> Self::Output {
-        L::over(&self.0, args.0, args.1)
     }
 }

src/lenses/first.rs

@@ -1,21 +1,21 @@
-use crate::lenses::{Lens, LensOver, LensView};
+use crate::{Lens, LensOver, LensTrait, LensView};
 
 #[derive(Clone, Copy)]
 pub struct _0Inner;
 pub const _0: Lens<_0Inner> = Lens(_0Inner);
+impl LensTrait for _0Inner {}
 
 macro_rules! make_tuples {
     ($f:ident, ( $( $v:ident ),* ), ( $( $t:ident ),* ) ) => {
       impl< $($t,)* > LensView<( $($t,)* )> for _0Inner {
             type Field = T;
 
-            fn view(&self, ( $($v,)* ): ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): ($($t,)*)) -> Self::Field {
                 $f
             }
         }
       impl< $($t,)* > LensOver<( $($t,)* )> for _0Inner {
             fn over<F>(
-                &self,
                 mut tup: ($($t,)*),
                 f: F
             ) -> ( $($t,)* )
@@ -30,14 +30,14 @@ macro_rules! make_tuples {
       impl<'a, $($t,)* > LensView<&'a ( $($t,)* )> for _0Inner {
             type Field = &'a T;
 
-            fn view(&self, ( $($v,)* ): &'a ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): &'a ($($t,)*)) -> Self::Field {
                 $f
             }
         }
       impl<'a, $($t,)* > LensView<&'a mut ( $($t,)* )> for _0Inner {
             type Field = &'a mut T;
 
-            fn view(&self, ( $($v,)* ): &'a mut ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): &'a mut ($($t,)*)) -> Self::Field {
                 $f
             }
         }
@@ -57,13 +57,12 @@ macro_rules! make_arrays {
       impl<T> LensView<[T; $n]> for _0Inner {
             type Field = T;
 
-            fn view(&self, [ $($v,)* ]: [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: [T; $n]) -> Self::Field {
                 $f
             }
         }
       impl<T> LensOver<[T; $n]> for _0Inner {
             fn over<F>(
-              &self,
               tup: [T; $n],
               fun: F
             ) -> [T; $n]
@@ -79,14 +78,14 @@ macro_rules! make_arrays {
       impl<'a, T> LensView<&'a [T; $n]> for _0Inner {
             type Field = &'a T;
 
-            fn view(&self, [ $($v,)* ]: &'a [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: &'a [T; $n]) -> Self::Field {
                 $f
             }
         }
       impl<'a, T> LensView<&'a mut [T; $n]> for _0Inner {
             type Field = &'a mut T;
 
-            fn view(&self, [ $($v,)* ]: &'a mut [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: &'a mut [T; $n]) -> Self::Field {
                 $f
             }
         }

src/lenses/identity.rs

@@ -1,19 +1,19 @@
-use crate::lenses::{Lens, LensOver, LensView};
+use crate::{LensOver, LensTrait, LensView};
 
+#[allow(non_camel_case_types)]
 #[derive(Clone, Copy)]
-pub struct IdInner;
+pub struct id;
-#[allow(non_upper_case_globals)]
-pub const id: Lens<IdInner> = Lens(IdInner);
 
-impl<T> LensView<T> for IdInner {
+impl LensTrait for id {}
+impl<T> LensView<T> for id {
     type Field = T;
 
-    fn view(&self, thing: T) -> Self::Field {
+    fn view(thing: T) -> Self::Field {
         thing
     }
 }
-impl<T> LensOver<T> for IdInner {
+impl<T> LensOver<T> for id {
-    fn over<F>(&self, thing: T, f: F) -> T
+    fn over<F>(thing: T, f: F) -> T
     where
         F: FnOnce(Self::Field) -> Self::Field,
     {

src/lenses/lens.rs

@@ -1,42 +0,0 @@
-use crate::lenses::{Lens, LensOver, LensView};
-
-type Getter<T, U> = dyn Fn(T) -> U;
-type Setter<T, U> = dyn Fn(T, U) -> T;
-
-pub struct FuncLens<T, U>(pub(crate) Box<Getter<T, U>>, pub(crate) Box<Setter<T, U>>);
-
-impl<T, U> LensView<T> for FuncLens<T, U> {
-    type Field = U;
-
-    fn view(&self, thing: T) -> Self::Field {
-        (self.0)(thing)
-    }
-}
-impl<T: Clone, U> LensOver<T> for FuncLens<T, U> {
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnOnce(Self::Field) -> Self::Field,
-    {
-        let v = f((self.0)(thing.clone()));
-        (self.1)(thing, v)
-    }
-
-    fn set(&self, thing: T, v: Self::Field) -> T {
-        (self.1)(thing, v)
-    }
-}
-
-/// Makes a lens that implements `LensView<T>` and `LensOver<T>` with the provided functions
-pub fn lens_from_boxed<T, U>(
-    getter: Box<Getter<T, U>>,
-    setter: Box<Setter<T, U>>,
-) -> Lens<FuncLens<T, U>> {
-    Lens(FuncLens(getter, setter))
-}
-/// Makes a lens that implements `LensView<T>` and `LensOver<T>` with the provided functions
-pub fn lens<T, U>(
-    getter: impl Fn(T) -> U + 'static,
-    setter: impl Fn(T, U) -> T + 'static,
-) -> Lens<FuncLens<T, U>> {
-    Lens(FuncLens(Box::new(getter), Box::new(setter)))
-}

src/lenses/mod.rs

@@ -5,221 +5,3 @@ mod first;
 pub use first::_0;
 mod second;
 pub use second::_1;
-
-mod to;
-pub use to::{to, to_from_boxed};
-mod lens;
-pub use lens::{lens, lens_from_boxed};
-
-/// Wrapper type
-#[derive(Clone, Copy)]
-#[repr(transparent)]
-pub struct Lens<L>(pub(crate) L);
-
-/// For lenses that allow viewing
-pub trait LensView<T> {
-    type Field;
-
-    fn view(&self, thing: T) -> Self::Field;
-}
-
-/// For lenses that allow setting
-pub trait LensOver<T>: LensView<T> {
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnOnce(Self::Field) -> Self::Field;
-
-    fn set(&self, thing: T, v: Self::Field) -> T {
-        Self::over(self, thing, |_| v)
-    }
-}
-
-impl<L, T> LensView<T> for Lens<L>
-where
-    L: LensView<T>,
-{
-    type Field = L::Field;
-
-    fn view(&self, thing: T) -> Self::Field {
-        L::view(&self.0, thing)
-    }
-}
-impl<L, T> LensOver<T> for Lens<L>
-where
-    L: LensOver<T>,
-{
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnOnce(Self::Field) -> Self::Field,
-    {
-        L::over(&self.0, thing, f)
-    }
-}
-
-pub fn view<T, L: LensView<T>>(lens: L, thing: T) -> L::Field {
-    L::view(&lens, thing)
-}
-pub fn set<T, L: LensOver<T>>(lens: L, thing: T, v: L::Field) -> T {
-    L::set(&lens, thing, v)
-}
-pub fn over<T, L: LensOver<T>>(lens: L, thing: T, f: impl FnOnce(L::Field) -> L::Field) -> T {
-    L::over(&lens, thing, f)
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn view_first_from_tuple() {
-        let a = (1, 2);
-        assert_eq!(view(_0, a), 1);
-
-        let a = (1, 2);
-        assert_eq!(view(_0, &a), &1);
-
-        let mut a = (1, 2);
-        assert_eq!(view(_0, &mut a), &mut 1);
-
-        let a = (1, 2, 3);
-        assert_eq!(view(_0, a), 1);
-
-        let a = (1, 2, 3);
-        assert_eq!(view(_0, &a), &1);
-    }
-
-    #[test]
-    fn view_first_from_tuple_mut_works() {
-        let mut a = (1, 2);
-        *view(_0, &mut a) += 1;
-
-        assert_eq!(a, (2, 2));
-    }
-
-    #[test]
-    fn set_first_from_tuple() {
-        let a = (1, 2);
-        let a = set(_0, a, 3);
-        assert_eq!(a, (3, 2));
-    }
-
-    #[test]
-    fn over_first_from_tuple() {
-        let a = (1, 2);
-        let a = over(_0, a, |v| v + 1);
-        assert_eq!(a, (2, 2));
-    }
-
-    #[test]
-    fn over_first_from_array() {
-        let a = [1, 2, 3, 4];
-
-        let a = over(_0, a, |v| v + 1);
-        assert_eq!(a, [2, 2, 3, 4]);
-    }
-
-    #[test]
-    fn second() {
-        let a = (1, 2);
-        let a = over(_1, a, |v| v + 1);
-        assert_eq!(a, (1, 3));
-
-        let a = [1, 2, 3, 4];
-        let a = over(_1, a, |v| v + 1);
-        assert_eq!(a, [1, 3, 3, 4]);
-    }
-
-    #[test]
-    fn call_as_funcs() {
-        let a = (1, 2);
-        assert_eq!(_0(a), 1);
-
-        let a = (1, 2);
-        assert_eq!(_0(a, |v| v + 1), (2, 2));
-
-        let a = ((1, 2), 3);
-
-        let res = _0(a);
-        assert_eq!(res, (1, 2));
-
-        let lens = _0 + _1;
-
-        let res = lens(a);
-        assert_eq!(res, 2);
-        let res = lens(a, |v| v + 1);
-        assert_eq!(res, ((1, 3), 3));
-    }
-
-    #[derive(Debug, PartialEq, Clone)]
-    struct Hello {
-        hey: u8,
-    }
-
-    #[test]
-    fn can_use_to() {
-        // making a getter
-        let l = to(|hello: Hello| hello.hey);
-
-        let hello = Hello { hey: 8 };
-        assert_eq!(l(hello), 8);
-    }
-
-    #[test]
-    fn can_make_lens_out_of_funcs() {
-        // making a lens
-        let l = lens(
-            |hello: Hello| hello.hey,
-            |mut hello: Hello, v: u8| {
-                hello.hey = v;
-                hello
-            },
-        );
-
-        let hello = Hello { hey: 8 };
-        assert_eq!(l(hello), 8);
-
-        let hello = Hello { hey: 8 };
-        assert_eq!(l(hello, |v| v + 1), Hello { hey: 9 });
-    }
-
-    #[test]
-    fn can_make_lens_out_of_to() {
-        // we first use to, and then use that to make a full lens
-
-        let l = to(|hello: Hello| hello.hey);
-        let l = l.make_lens(|mut hello: Hello, v: u8| {
-            hello.hey = v;
-            hello
-        });
-
-        let hello = Hello { hey: 8 };
-        assert_eq!(l(hello), 8);
-
-        let hello = Hello { hey: 8 };
-        assert_eq!(l(hello, |v| v + 1), Hello { hey: 9 });
-    }
-
-    #[test]
-    fn convoluted_example() {
-        #[derive(Debug, PartialEq, Clone)]
-        struct Hello2 {
-            hey: (u8, (u8, i32)),
-        }
-
-        // make a lens for Hello
-        let l = lens(
-            |hello: Hello2| hello.hey,
-            |mut hello: Hello2, v| {
-                hello.hey = v;
-                hello
-            },
-        );
-
-        let thing = Hello2 { hey: (1, (2, -3)) };
-        let thing = (thing, "hello");
-
-        let lens_that_targets_the_i32 = _0 + l + _1 + _1;
-
-        assert_eq!(lens_that_targets_the_i32(thing), -3);
-    }
-}

src/lenses/second.rs

@@ -1,21 +1,21 @@
-use crate::lenses::{Lens, LensOver, LensView};
+use crate::{Lens, LensOver, LensTrait, LensView};
 
 #[derive(Clone, Copy)]
 pub struct _1Inner;
 pub const _1: Lens<_1Inner> = Lens(_1Inner);
+impl LensTrait for _1Inner {}
 
 macro_rules! make_tuples {
     ($f:ident, ( $( $v:ident ),* ), ( $( $t:ident ),* ) ) => {
       impl< $($t,)* > LensView<( $($t,)* )> for _1Inner {
             type Field = T;
 
-            fn view(&self, ( $($v,)* ): ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): ($($t,)*)) -> Self::Field {
                 $f
             }
         }
       impl< $($t,)* > LensOver<( $($t,)* )> for _1Inner {
             fn over<F>(
-                &self,
                 mut tup: ($($t,)*),
                 f: F
             ) -> ( $($t,)* )
@@ -30,14 +30,14 @@ macro_rules! make_tuples {
       impl<'a, $($t,)* > LensView<&'a ( $($t,)* )> for _1Inner {
             type Field = &'a T;
 
-            fn view(&self, ( $($v,)* ): &'a ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): &'a ($($t,)*)) -> Self::Field {
                 $f
             }
         }
       impl<'a, $($t,)* > LensView<&'a mut ( $($t,)* )> for _1Inner {
             type Field = &'a mut T;
 
-            fn view(&self, ( $($v,)* ): &'a mut ($($t,)*)) -> Self::Field {
+            fn view(( $($v,)* ): &'a mut ($($t,)*)) -> Self::Field {
                 $f
             }
         }
@@ -57,13 +57,12 @@ macro_rules! make_arrays {
       impl<T> LensView<[T; $n]> for _1Inner {
             type Field = T;
 
-            fn view(&self, [ $($v,)* ]: [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: [T; $n]) -> Self::Field {
                 $f
             }
         }
       impl<T> LensOver<[T; $n]> for _1Inner {
             fn over<F>(
-              &self,
               tup: [T; $n],
               fun: F
             ) -> [T; $n]
@@ -79,14 +78,14 @@ macro_rules! make_arrays {
       impl<'a, T> LensView<&'a [T; $n]> for _1Inner {
             type Field = &'a T;
 
-            fn view(&self, [ $($v,)* ]: &'a [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: &'a [T; $n]) -> Self::Field {
                 $f
             }
         }
       impl<'a, T> LensView<&'a mut [T; $n]> for _1Inner {
             type Field = &'a mut T;
 
-            fn view(&self, [ $($v,)* ]: &'a mut [T; $n]) -> Self::Field {
+            fn view([ $($v,)* ]: &'a mut [T; $n]) -> Self::Field {
                 $f
             }
         }

src/lenses/to.rs

@@ -1,29 +0,0 @@
-use crate::lenses::{Lens, LensView};
-
-use super::lens::FuncLens;
-
-pub struct ToInner<T, U>(Box<dyn Fn(T) -> U>);
-
-impl<T, U> LensView<T> for ToInner<T, U> {
-    type Field = U;
-
-    fn view(&self, thing: T) -> Self::Field {
-        (self.0)(thing)
-    }
-}
-
-/// Makes a lens that implements `LensView<T>` with the provided function
-pub fn to_from_boxed<T, U>(f: Box<dyn Fn(T) -> U>) -> Lens<ToInner<T, U>> {
-    Lens(ToInner(f))
-}
-/// Makes a lens that implements `LensView<T>` with the provided function
-pub fn to<T, U>(f: impl Fn(T) -> U + 'static) -> Lens<ToInner<T, U>> {
-    Lens(ToInner(Box::new(f)))
-}
-
-impl<T, U> Lens<ToInner<T, U>> {
-    /// Makes a full lens that implements `LensView<T>` and `LensOver<T>` with the provided functions
-    pub fn make_lens(self, setter: impl Fn(T, U) -> T + 'static) -> Lens<FuncLens<T, U>> {
-        Lens(FuncLens((self.0).0, Box::new(setter)))
-    }
-}

src/lib.rs

@@ -1,7 +1,173 @@
 #![feature(unboxed_closures, fn_traits)]
 
+/// Base trait
+pub trait LensTrait {}
+
+/// For lenses that allow viewing
+pub trait LensView<T>: LensTrait {
+    type Field;
+
+    fn view(thing: T) -> Self::Field;
+}
+
+/// For lenses that allow setting
+pub trait LensOver<T>: LensView<T> {
+    fn over<F>(thing: T, f: F) -> T
+    where
+        F: FnOnce(Self::Field) -> Self::Field;
+
+    fn set(thing: T, v: Self::Field) -> T {
+        Self::over(thing, |_| v)
+    }
+}
+
+/// Wrapper type
+#[derive(Clone, Copy)]
+pub struct Lens<T: LensTrait>(T);
+
+impl<L: LensTrait> LensTrait for Lens<L> {}
+impl<L, T> LensView<T> for Lens<L>
+where
+    L: LensView<T>,
+{
+    type Field = L::Field;
+
+    fn view(thing: T) -> Self::Field {
+        L::view(thing)
+    }
+}
+impl<L, T> LensOver<T> for Lens<L>
+where
+    L: LensOver<T>,
+{
+    fn over<F>(thing: T, f: F) -> T
+    where
+        F: FnOnce(Self::Field) -> Self::Field,
+    {
+        L::over(thing, f)
+    }
+}
+
+pub fn view<T, L: LensView<T>>(_lens: L, thing: T) -> L::Field {
+    L::view(thing)
+}
+pub fn set<T, L: LensOver<T>>(_lens: L, thing: T, v: L::Field) -> T {
+    L::set(thing, v)
+}
+pub fn over<T, L: LensOver<T>>(_lens: L, thing: T, f: impl FnOnce(L::Field) -> L::Field) -> T {
+    L::over(thing, f)
+}
+
+// TODO add fn impls
+
+// TODO add third_from_tuple, etc
+
+// TODO array traversals
+
+// TODO make over work with changing types
+
 mod combinations;
 mod fns;
 pub mod lenses;
-pub mod prisms;
+
-pub mod traversals;
+#[cfg(test)]
+mod tests {
+    use super::{
+        lenses::{_0, _1},
+        *,
+    };
+
+    #[test]
+    fn view_first_from_tuple() {
+        let a = (1, 2);
+        assert_eq!(view(_0, a), 1);
+
+        let a = (1, 2);
+        assert_eq!(view(_0, &a), &1);
+
+        let mut a = (1, 2);
+        assert_eq!(view(_0, &mut a), &mut 1);
+
+        let a = (1, 2, 3);
+        assert_eq!(view(_0, a), 1);
+
+        let a = (1, 2, 3);
+        assert_eq!(view(_0, &a), &1);
+    }
+
+    #[test]
+    fn view_first_from_tuple_mut_works() {
+        let mut a = (1, 2);
+        *view(_0, &mut a) += 1;
+
+        assert_eq!(a, (2, 2));
+    }
+
+    #[test]
+    fn set_first_from_tuple() {
+        let a = (1, 2);
+        let a = set(_0, a, 3);
+        assert_eq!(a, (3, 2));
+    }
+
+    #[test]
+    fn over_first_from_tuple() {
+        let a = (1, 2);
+        let a = over(_0, a, |v| v + 1);
+        assert_eq!(a, (2, 2));
+    }
+
+    #[test]
+    fn over_first_from_array() {
+        let a = [1, 2, 3, 4];
+
+        let a = over(_0, a, |v| v + 1);
+        assert_eq!(a, [2, 2, 3, 4]);
+    }
+
+    #[test]
+    fn second() {
+        let a = (1, 2);
+        let a = over(_1, a, |v| v + 1);
+        assert_eq!(a, (1, 3));
+
+        let a = [1, 2, 3, 4];
+        let a = over(_1, a, |v| v + 1);
+        assert_eq!(a, [1, 3, 3, 4]);
+    }
+
+    #[test]
+    fn view_combination() {
+        let a = ((1, 2), 3);
+
+        let lens = _0 + _1;
+        let a = view(lens, a);
+        assert_eq!(a, 2);
+    }
+
+    #[test]
+    fn over_combination() {
+        let a = ((1, 2), 3);
+
+        let lens = _0 + _1;
+        let a = over(lens, a, |v| v + 1);
+        assert_eq!(a, ((1, 3), 3));
+    }
+
+    #[test]
+    fn call_as_funcs() {
+        let a = (1, 2);
+        assert_eq!(_0(a), 1);
+
+        let a = (1, 2);
+        assert_eq!(_0(a, |v| v + 1), (2, 2));
+
+        let a = ((1, 2), 3);
+        let lens = _0 + _1;
+
+        let res = lens(a);
+        assert_eq!(res, 2);
+        let res = lens(a, |v| v + 1);
+        assert_eq!(res, ((1, 3), 3));
+    }
+}

src/prisms/mod.rs

@@ -1,121 +0,0 @@
-mod result;
-pub use result::{_Err, _Ok};
-
-mod option;
-pub use option::{_None, _Some};
-
-/// Wrapper type
-#[derive(Clone, Copy)]
-#[repr(transparent)]
-pub struct Prism<P>(pub(crate) P);
-
-pub trait PrismPreview<T> {
-    type Field;
-
-    fn preview(&self, thing: T) -> Option<Self::Field>;
-    fn review(&self, thing: Self::Field) -> T;
-
-    // TODO id like for this to not need clone
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnOnce(Self::Field) -> Self::Field,
-        T: Clone,
-    {
-        if let Some(a) = Self::preview(&self, thing.clone()) {
-            Self::review(&self, f(a))
-        } else {
-            thing
-        }
-    }
-
-    fn set(&self, thing: T, v: Self::Field) -> T
-    where
-        T: Clone,
-        Self::Field: Clone,
-    {
-        Self::over(self, thing, move |_| v.clone())
-    }
-}
-
-impl<P, T> PrismPreview<T> for Prism<P>
-where
-    P: PrismPreview<T>,
-{
-    type Field = P::Field;
-
-    fn preview(&self, thing: T) -> Option<Self::Field> {
-        P::preview(&self.0, thing)
-    }
-
-    fn review(&self, thing: Self::Field) -> T {
-        P::review(&self.0, thing)
-    }
-}
-
-pub fn preview<T, P: PrismPreview<T>>(prism: P, thing: T) -> Option<P::Field> {
-    P::preview(&prism, thing)
-}
-pub fn review<T, P: PrismPreview<T>>(prism: P, thing: P::Field) -> T {
-    P::review(&prism, thing)
-}
-pub fn over<T: Clone, P: PrismPreview<T>>(
-    prism: P,
-    thing: T,
-    f: impl FnOnce(P::Field) -> P::Field,
-) -> T {
-    P::over(&prism, thing, f)
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn preview_result() {
-        let a: Result<i32, i32> = Ok(3);
-        assert_eq!(_Ok(a), Some(3));
-
-        let a: Result<i32, i32> = Err(3);
-        assert_eq!(preview(_Ok, a), None);
-
-        let a: Result<i32, i32> = Ok(3);
-        assert_eq!(_Err(a), None);
-
-        let a: Result<i32, i32> = Err(3);
-        assert_eq!(preview(_Err, a), Some(3));
-    }
-
-    #[test]
-    fn preview_option() {
-        let a = Some(3);
-        assert_eq!(_Some(a), Some(3));
-
-        let a = Some(3);
-        assert_eq!(preview(_None, a), Some(()));
-
-        let a: Option<i32> = None;
-        assert_eq!(preview(_Some, a), None);
-
-        let a: Option<i32> = None;
-        assert_eq!(preview(_None, a), Some(()));
-    }
-
-    #[test]
-    fn review_result() {
-        assert_eq!(review(_Ok, 3), Ok::<i32, i32>(3));
-        assert_eq!(review(_Err, 3), Err::<i32, i32>(3));
-    }
-
-    #[test]
-    fn review_option() {
-        assert_eq!(review(_Some, 3), Some(3));
-        assert_eq!(review(_None, ()), None::<()>);
-    }
-
-    #[test]
-    fn over_option() {
-        assert_eq!(over(_Some, Some(3), |v| v + 1), Some(4));
-        assert_eq!(_Some(Some(3), |v| v + 1), Some(4));
-        assert_eq!(over(_None, None, |_v: ()| ()), None::<()>);
-    }
-}

src/prisms/option.rs

@@ -1,34 +0,0 @@
-use super::*;
-
-#[derive(Clone, Copy)]
-pub struct SomeInner;
-#[allow(non_upper_case_globals)]
-pub const _Some: Prism<SomeInner> = Prism(SomeInner);
-
-impl<T> PrismPreview<Option<T>> for SomeInner {
-    type Field = T;
-
-    fn preview(&self, thing: Option<T>) -> Option<Self::Field> {
-        thing
-    }
-
-    fn review(&self, thing: Self::Field) -> Option<T> {
-        Some(thing)
-    }
-}
-
-#[derive(Clone, Copy)]
-pub struct NoneInner;
-#[allow(non_upper_case_globals)]
-pub const _None: Prism<NoneInner> = Prism(NoneInner);
-impl<T> PrismPreview<Option<T>> for NoneInner {
-    type Field = ();
-
-    fn preview(&self, _thing: Option<T>) -> Option<Self::Field> {
-        Some(())
-    }
-
-    fn review(&self, _thing: Self::Field) -> Option<T> {
-        None
-    }
-}

src/prisms/result.rs

@@ -1,32 +0,0 @@
-use super::*;
-
-#[derive(Clone, Copy)]
-pub struct OkInner;
-#[allow(non_upper_case_globals)]
-pub const _Ok: Prism<OkInner> = Prism(OkInner);
-impl<T, E> PrismPreview<Result<T, E>> for OkInner {
-    type Field = T;
-
-    fn preview(&self, thing: Result<T, E>) -> Option<Self::Field> {
-        thing.ok()
-    }
-    fn review(&self, thing: Self::Field) -> Result<T, E> {
-        Ok(thing)
-    }
-}
-
-#[derive(Clone, Copy)]
-pub struct ErrInner;
-#[allow(non_upper_case_globals)]
-pub const _Err: Prism<ErrInner> = Prism(ErrInner);
-
-impl<T, E> PrismPreview<Result<T, E>> for ErrInner {
-    type Field = E;
-
-    fn preview(&self, thing: Result<T, E>) -> Option<Self::Field> {
-        thing.err()
-    }
-    fn review(&self, thing: Self::Field) -> Result<T, E> {
-        Err(thing)
-    }
-}

src/traversals/both.rs

@@ -1,23 +0,0 @@
-use crate::traversals::{Traversal, TraversalOver, TraversalTraverse};
-
-#[derive(Clone, Copy)]
-pub struct BothInner;
-#[allow(non_upper_case_globals)]
-pub const both: Traversal<BothInner> = Traversal(BothInner);
-
-impl<T> TraversalTraverse<(T, T)> for BothInner {
-    type Field = T;
-
-    fn traverse(&self, (a, b): (T, T)) -> Vec<Self::Field> {
-        vec![a, b]
-    }
-}
-
-impl<T> TraversalOver<(T, T)> for BothInner {
-    fn over<F>(&self, (a, b): (T, T), mut f: F) -> (T, T)
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        (f(a), f(b))
-    }
-}

src/traversals/each.rs

@@ -1,146 +0,0 @@
-use crate::traversals::{Traversal, TraversalOver, TraversalTraverse};
-
-#[derive(Clone, Copy)]
-pub struct EachInner;
-#[allow(non_upper_case_globals)]
-pub const each: Traversal<EachInner> = Traversal(EachInner);
-
-impl<T> TraversalTraverse<Vec<T>> for EachInner {
-    type Field = T;
-
-    fn traverse(&self, thing: Vec<T>) -> Vec<Self::Field> {
-        thing
-    }
-}
-impl<T> TraversalOver<Vec<T>> for EachInner {
-    fn over<F>(&self, thing: Vec<T>, f: F) -> Vec<T>
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        thing.into_iter().map(f).collect()
-    }
-}
-
-// TODO i'd like to have this so we get it for free on any iterable
-// problem is, arrays/tuples don't implement FromIter
-// and having both the blanket implementation and the one below complains cause
-// other crates could add the trait in the future
-
-// impl<I, T> TraversalTraverse<I> for EachInner
-// where
-//     I: IntoIterator<Item = T>,
-// {
-//     type Field = T;
-
-//     fn traverse(&self, thing: I) -> Vec<Self::Field> {
-//         thing.into_iter().collect()
-//     }
-// }
-
-// impl<I, T> TraversalOver<I> for EachInner
-// where
-//     I: IntoIterator<Item = T> + FromIterator<T>,
-// {
-//     fn over<F>(&self, thing: I, f: F) -> I
-//     where
-//         F: FnMut(Self::Field) -> Self::Field,
-//     {
-//         thing.into_iter().map(f).collect()
-//     }
-// }
-
-macro_rules! make_tuples {
-    ($f:ident, ( $( $v:ident ),* ), ( $( $t:ident ),* ) ) => {
-        impl<T> TraversalTraverse<( $($t,)* )> for EachInner {
-            type Field = T;
-
-            fn traverse(&self, ( $($v,)* ): ($($t,)*)) -> Vec<Self::Field> {
-                vec![ $($v,)* ]
-            }
-        }
-        impl<T> TraversalOver<( $($t,)* )> for EachInner {
-            fn over<F>(
-                &self,
-                ($($v,)*): ($($t,)*),
-                mut f: F
-            ) -> ( $($t,)* )
-            where
-              F: FnMut(Self::Field) -> Self::Field
-            {
-
-              ( $( f($v), )* )
-            }
-        }
-
-        impl<'a, T> TraversalTraverse<&'a ( $($t,)* )> for EachInner {
-            type Field = &'a T;
-
-            fn traverse(&self, ( $($v,)* ): &'a ($($t,)*)) -> Vec<Self::Field> {
-                vec![ $($v,)* ]
-            }
-        }
-        impl<'a, T> TraversalTraverse<&'a mut ( $($t,)* )> for EachInner {
-            type Field = &'a mut T;
-
-            fn traverse(&self, ( $($v,)* ): &'a mut ($($t,)*)) -> Vec<Self::Field> {
-              vec![ $($v,)* ]
-            }
-        }
-    };
-}
-
-make_tuples!(t, (t), (T));
-make_tuples!(t, (t, u), (T, T));
-make_tuples!(t, (t, u, v), (T, T, T));
-make_tuples!(t, (t, u, v, w), (T, T, T, T));
-make_tuples!(t, (t, u, v, w, x), (T, T, T, T, T));
-make_tuples!(t, (t, u, v, w, x, y), (T, T, T, T, T, T));
-make_tuples!(t, (t, u, v, w, x, y, z), (T, T, T, T, T, T, T));
-// not doing more cause i'm lazy, open a pr if you need more :)
-
-macro_rules! make_arrays {
-    ($f:ident, $n:expr, [$( $v:ident ),*]) => {
-      impl<T> TraversalTraverse<[T; $n]> for EachInner {
-            type Field = T;
-
-            fn traverse(&self, [ $($v,)* ]: [T; $n]) -> Vec<Self::Field> {
-                vec![ $($v,)* ]
-            }
-        }
-      impl<T> TraversalOver<[T; $n]> for EachInner {
-            fn over<F>(
-              &self,
-              [ $($v,)* ]: [T; $n],
-              mut fun: F
-            ) -> [T; $n]
-            where
-              F: FnMut(Self::Field) -> Self::Field
-            {
-              [$(fun($v),)*]
-            }
-        }
-
-      impl<'a, T> TraversalTraverse<&'a [T; $n]> for EachInner {
-            type Field = &'a T;
-
-            fn traverse(&self, [ $($v,)* ]: &'a [T; $n]) -> Vec<Self::Field> {
-                vec![ $($v,)* ]
-            }
-        }
-      impl<'a, T> TraversalTraverse<&'a mut [T; $n]> for EachInner {
-            type Field = &'a mut T;
-
-            fn traverse(&self, [ $($v,)* ]: &'a mut [T; $n]) -> Vec<Self::Field> {
-                vec![ $($v,)* ]
-            }
-        }
-    };
-}
-
-make_arrays!(t, 1, [t]);
-make_arrays!(t, 2, [t, _a]);
-make_arrays!(t, 3, [t, _a, _b]);
-make_arrays!(t, 4, [t, _a, _b, _c]);
-make_arrays!(t, 5, [t, _a, _b, _c, _d]);
-make_arrays!(t, 6, [t, _a, _b, _c, _d, _e]);
-make_arrays!(t, 7, [t, _a, _b, _c, _d, _e, _g]);

src/traversals/mod.rs

@@ -1,157 +0,0 @@
-mod both;
-pub use both::both;
-
-mod each;
-pub use each::each;
-
-use crate::{
-    lenses::{Lens, LensOver, LensView},
-    prisms::{Prism, PrismPreview},
-};
-
-/// Wrapper type
-#[derive(Clone, Copy)]
-#[repr(transparent)]
-pub struct Traversal<T>(pub(crate) T);
-
-pub trait TraversalTraverse<T> {
-    type Field;
-
-    fn traverse(&self, thing: T) -> Vec<Self::Field>;
-}
-pub trait TraversalOver<T>: TraversalTraverse<T> {
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnMut(Self::Field) -> Self::Field;
-
-    fn set(&self, thing: T, v: Self::Field) -> T
-    where
-        Self::Field: Clone,
-    {
-        Self::over(self, thing, move |_| v.clone())
-    }
-}
-
-impl<L, T> TraversalTraverse<T> for Traversal<L>
-where
-    L: TraversalTraverse<T>,
-{
-    type Field = L::Field;
-
-    fn traverse(&self, thing: T) -> Vec<Self::Field> {
-        L::traverse(&self.0, thing)
-    }
-}
-impl<L, T> TraversalOver<T> for Traversal<L>
-where
-    L: TraversalOver<T>,
-{
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        L::over(&self.0, thing, f)
-    }
-}
-
-// all lenses are traversals, so we can freely transform them into a traversal
-impl<L> Lens<L> {
-    /// Returns this lens as a traversal
-    pub fn to_traversal(self) -> Traversal<Lens<L>> {
-        Traversal(self)
-    }
-}
-// we can go back to a lens from a "traversal-ed" lens
-impl<L> Traversal<Lens<L>> {
-    /// Returns the wrapped lens
-    pub fn to_lens(self) -> Lens<L> {
-        self.0
-    }
-}
-impl<L, T> TraversalTraverse<T> for Lens<L>
-where
-    L: LensView<T>,
-{
-    type Field = L::Field;
-
-    fn traverse(&self, thing: T) -> Vec<Self::Field> {
-        vec![L::view(&self.0, thing)]
-    }
-}
-impl<L, T> TraversalOver<T> for Lens<L>
-where
-    L: LensView<T> + LensOver<T>,
-{
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        L::over(&self.0, thing, f)
-    }
-}
-
-// all prisms are traversals, so we can freely transform them into a traversal
-impl<L> Prism<L> {
-    /// Returns this lens as a traversal
-    pub fn to_traversal(self) -> Traversal<Prism<L>> {
-        Traversal(self)
-    }
-}
-// we can go back to a lens from a "traversal-ed" lens
-impl<L> Traversal<Prism<L>> {
-    /// Returns the wrapped lens
-    pub fn to_prism(self) -> Prism<L> {
-        self.0
-    }
-}
-impl<L, T> TraversalTraverse<T> for Prism<L>
-where
-    L: PrismPreview<T>,
-{
-    type Field = L::Field;
-
-    fn traverse(&self, thing: T) -> Vec<Self::Field> {
-        L::preview(&self.0, thing).into_iter().collect()
-    }
-}
-impl<L, T> TraversalOver<T> for Prism<L>
-where
-    T: Clone,
-    L: PrismPreview<T>,
-{
-    fn over<F>(&self, thing: T, f: F) -> T
-    where
-        F: FnMut(Self::Field) -> Self::Field,
-    {
-        L::over(&self.0, thing, f)
-    }
-}
-
-pub fn traverse<T, L: TraversalTraverse<T>>(lens: L, thing: T) -> Vec<L::Field> {
-    L::traverse(&lens, thing)
-}
-pub fn set<T, L: TraversalOver<T>>(lens: L, thing: T, v: L::Field) -> T
-where
-    <L as TraversalTraverse<T>>::Field: Clone,
-{
-    L::set(&lens, thing, v)
-}
-pub fn over<T, L: TraversalOver<T>>(lens: L, thing: T, f: impl FnMut(L::Field) -> L::Field) -> T {
-    L::over(&lens, thing, f)
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn traverse_each_works_on_arrays() {
-        let array = [1, 2, 3, 4];
-
-        let res = each(array);
-        assert_eq!(res, vec![1, 2, 3, 4,]);
-
-        let res = each(array, |v| v + 1);
-        assert_eq!(res, [2, 3, 4, 5]);
-    }
-}