Initial data commit

Task/Parametric-polymorphism/Rust/parametric-polymorphism.rust

@@ -0,0 +1,46 @@
+struct TreeNode<T> {
+    value: T,
+    left: Option<Box<TreeNode<T>>>,
+    right: Option<Box<TreeNode<T>>>,
+}
+
+impl <T> TreeNode<T> {
+    fn my_map<U,F>(&self, f: &F) -> TreeNode<U> where
+            F: Fn(&T) -> U {
+        TreeNode {
+            value: f(&self.value),
+            left: match self.left {
+                None => None,
+                Some(ref n) => Some(Box::new(n.my_map(f))),
+            },
+            right: match self.right {
+                None => None,
+                Some(ref n) => Some(Box::new(n.my_map(f))),
+            },
+        }
+    }
+}
+
+fn main() {
+    let root = TreeNode {
+        value: 3,
+        left: Some(Box::new(TreeNode {
+            value: 55,
+            left: None,
+            right: None,
+        })),
+        right: Some(Box::new(TreeNode {
+            value: 234,
+            left: Some(Box::new(TreeNode {
+                value: 0,
+                left: None,
+                right: None,
+            })),
+            right: None,
+        })),
+    };
+    root.my_map(&|x| { println!("{}" , x)});
+    println!("---------------");
+    let new_root = root.my_map(&|x| *x as f64 * 333.333f64);
+    new_root.my_map(&|x| { println!("{}" , x) });
+}