add arrays to _0

src/lenses/first.rs

@@ -48,3 +48,51 @@ make_tuples!(t, (t, _u, _v, _w, _x), (T, U, V, W, X));
 make_tuples!(t, (t, _u, _v, _w, _x, _y), (T, U, V, W, X, Y));
 make_tuples!(t, (t, _u, _v, _w, _x, _y, _z), (T, U, V, W, X, Y, Z));
 // 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> LensView<[T; $n]> for _0 {
+            type Field = T;
+
+            fn view([ $($v,)* ]: [T; $n]) -> Self::Field {
+                $f
+            }
+        }
+        impl<T> LensOver<[T; $n]> for _0 {
+            fn over<F>(
+              tup: [T; $n],
+              fun: F
+            ) -> [T; $n]
+            where
+              F: FnOnce(Self::Field) -> Self::Field
+            {
+              let [$($v,)*] = tup;
+              let $f = fun( $f );
+              [$($v,)*]
+            }
+        }
+
+        impl<'a, T> LensView<&'a [T; $n]> for _0 {
+            type Field = &'a T;
+
+            fn view([ $($v,)* ]: &'a [T; $n]) -> Self::Field {
+                $f
+            }
+        }
+        impl<'a, T> LensView<&'a mut [T; $n]> for _0 {
+            type Field = &'a mut T;
+
+            fn view([ $($v,)* ]: &'a mut [T; $n]) -> Self::Field {
+                $f
+            }
+        }
+    };
+}
+
+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/lib.rs

@@ -84,11 +84,19 @@ mod tests {
     #[test]
     fn over_first_from_tuple() {
         let a = (1, 2);
-        let a = over(_0, a, &|v| v + 1);
+        let a = over(_0, a, |v| v + 1);
         assert_eq!(a, (2, 2));
 
         let a = (1, 2);
-        let a = _0::over(a, &|v| v + 1);
+        let a = _0::over(a, |v| v + 1);
         assert_eq!(a, (2, 2));
     }
+
+    #[test]
+    fn over_first_from_array() {
+        let a = [1, 2, 3, 4];
+
+        let a = _0::over(a, |v| v + 1);
+        assert_eq!(a, [2, 2, 3, 4]);
+    }
 }