--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/patterns.rs	Sat Jan 01 18:18:17 2022 +1000
@@ -0,0 +1,25 @@
+use memoize::memoize;
+
+// Patterns in memoized function arguments must be bound by name.
+#[memoize]
+fn manhattan_distance(_p1 @ (x1, y1): (i32, i32), _p2 @ (x2, y2): (i32, i32)) -> i32 {
+    (x1 - x2).abs() + (y1 - y2).abs()
+}
+
+#[derive(Clone, PartialEq, Eq, Hash)]
+enum OnlyOne {
+    Value(i32),
+}
+
+#[memoize]
+fn get_value(_enum @ OnlyOne::Value(value): OnlyOne) -> i32 {
+    value
+}
+
+fn main() {
+    // `manhattan_distance` is only called once here.
+    assert_eq!(manhattan_distance((1, 1), (1, 3)), 2);
+    
+    // Same with `get_value`.
+    assert_eq!(!get_value(OnlyOne::Value(0)), 0);
+}