Updated: Readme

README.md

@@ -145,8 +145,8 @@ This will load on top of your syntax highlighting for every .c file.
 </div>
 
 <div align="center">
-  <b> Enums </b>
-  <img src="docs/imgs/enums/enum_preview1_fn.png">
+  <b> Binary tree & Enums </b>
+  <img src="docs/imgs/example/enum_binary_tree.png">
 </div>
 
 <div align="center">

examples/enum/binarytree.c

@@ -0,0 +1,30 @@
+    #include <stdio.h>
+    #include <z_/z_.h>
+
+    z__Enum(
+        BinaryTree,
+            (Leaf, int),
+            (Node, BinaryTree *, int, BinaryTree *)
+        );
+
+    int sum(const BinaryTree *tree) {                           /*        6     */
+        match(*tree) {                                          /*       /\     */
+            slot(Leaf, x)                                       /*      2 7     */
+                return *x; unslot;                              /*     /\       */
+            slot(Node, lhs, x, rhs)                             /*    1 4       */
+                return sum(*lhs) + *x + sum(*rhs); unslot;      /*      /\      */
+        }                                                       /*     3 5      */
+        return 0;
+    }
+
+    #define TREE(tree)                 ((BinaryTree *)(BinaryTree[]){tree})
+    #define NODE(left, numbe30, right) TREE(Node(left, numbe30, right))
+    #define LEAF(number)               TREE(Leaf(number))
+
+    int main(int argc, char ** argv)
+    {
+        const BinaryTree *tree =
+            NODE(NODE(LEAF(1), 2, NODE(LEAF(3), 4, LEAF(5))), 6, LEAF(7));
+
+        printf("%d\n", sum(tree)); // 28 
+    }