examples and tests

examples/main.rs

@@ -31,5 +31,5 @@ fn main() {
 
     // you can also call the lens as a function to modify the value
     let res = lens(a, |v| v + 1);
-    assert_eq!(res, ((1, 3), 3));
+    assert_eq!(res, ((1, 6), 3));
 }

examples/struct_fields.rs

@@ -0,0 +1,27 @@
+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/lenses/mod.rs

@@ -213,4 +213,28 @@ mod tests {
         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/prisms/mod.rs

@@ -88,7 +88,4 @@ mod tests {
         assert_eq!(review(_Some, 3), Some(3));
         assert_eq!(review(_None, ()), None::<()>);
     }
-
-    #[test]
-    fn view_combination() {}
 }