initial laptop commit

examples/access-macro.rs

@@ -0,0 +1,63 @@
+macro_rules! access {
+    ($instance: expr, $trait: path, $with: expr) => {
+        {
+            fn get_thing<T: $trait>(instance: &T) {
+                $with(<T as $trait>::Type)
+            }
+
+            get_thing($instance)
+        }
+    }
+}
+
+struct Cat;
+struct Dog;
+
+trait Animal {
+    type Type;
+}
+
+impl Animal for Cat {
+    type Type = u32;
+}
+
+impl Animal for Dog {
+    type Type = i64;
+}
+
+trait MaxAndMin {
+    type Type;
+    const MAXIMUM: Self::Type;
+    const MINIMUM: Self::Type;
+}
+
+impl MaxAndMin for u32 {
+    type Type = u32;
+    const MAXIMUM: Self::Type = u32::MAX;
+    const MINIMUM: Self::Type = u32::MIN;
+}
+
+impl MaxAndMin for i64 {
+    type Type = i64;
+    const MAXIMUM: Self::Type = i64::MAX;
+    const MINIMUM: Self::Type = i64::MIN;
+}
+
+fn main() {
+    let katniss = Cat;
+    let lola = Dog;
+
+    fn get_min<T: Animal>(instance: &T) -> <<T as Animal>::Type as MaxAndMin>::Type where T::Type: MaxAndMin {
+        <T::Type as MaxAndMin>::MINIMUM
+    }
+
+    let katniss_max = get_min(&katniss);
+    let lola_max = get_min(&lola);
+
+    println!("{katniss_max}");
+    println!("{lola_max}");
+
+    // let max = access!(&katniss, Animal, ::MAX);
+
+    // println!("{legs}");
+}